Mindful Lawyer Study

Note: This script was written using versions 3.4.3 and 1.1.414 of R and RStudio, respectively.

Project Components

The study described in this document is part of a larger project looking at the effects of mindfulness in the legal profession. In addition to this script, the following project components are publicly available:

• Pilot Study: Full Analysis
• Pilot Study: Analysis Summary
• Main Study: Full Analysis
• Main Study: Analysis Summary
• Main Study: OSF Pre-Registration

Abstract

This study investigated the effects of a mindfulness meditation intervention on the psychological well-being and self-perceived competency of a group of lawyers. One hundred lawyers were randomly assigned to either an experimental group or a delayed-start control group (n = 50 in each). All participants completed a series of self-report measures designed to assess perceived well-being, affect, and job competency (T1). Following the completion of these measures, the experimental group participated in a 30-day mindfulness program. At the end of this program, all participants completed the self-report measures for a second time (T2). The control group then participated in the same 30-day mindfulness program and, at the end of this program, all participants completed the self-report measures for a third and final time (T3). The completion of the mindfulness program was associated with significant decreases in stress, negative affect, and depression, as well as increases in positive affect, non-reactivity, observing, acting with awareness, non-judging, and perceived job effectiveness. These changes failed to decrease participants’ level of perceived stress to levels experienced by the general population. Nevertheless, significant changes in both groups were observed, suggesting that the intervention was effective in enhancing participants’ mindfulness and improving their psychological well-being. Based on correlation and moderation analyses, most improvements seem to have been unrelated to the amount of program engagement (i.e. the amount of time spent meditating throughout the 30-day program) and length of previous meditation experience. It is, however, important to note that the samples that were ultimately analyzed were relatively small due to participant drop-out throughout the study. Consequently, though the significant findings and general trends within the data are promising, these results should be interpreted with caution and future work should consider ways in which drop-out can be minimized or mitigated.

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Introduction

This document outlines the analyses from the Mindful Lawyer Study. Research protocol and planned analyses for this study were registered by Minda and Nielsen and can be viewed here. The purpose of this study was to investigate whether a 30-day mindfulness intervention would improve the well-being of a group of lawyers.

Participants were randomly assigned to one of two conditions: an experimental condition or a delayed-start control condition (n = 50 for both). At the beginning of the study (i.e. T1), all participants were asked to complete a series of self-report measures:

• The Perceived Stress Scale (PSS; Cohen et al., 1983), which provides a measure of perceived stress.

• The Positive and Negative Affect Schedule (PANAS; Watson et al., 1988), which provides a measure of both current positive (POS) and current negative (NEG) mood.

• The Brief Resilience Scale (BRS; Smith et al., 2008), which provides a measure of psychological resilience.

• The Five Facet Mindfulness Questionnaire-Short Form (FFMQ; Baer et al., 2008; Bohlmeijer et al., 2011), which provides a measure of five aspects of mindful cognition: non-reactivity to inner experience (NR), observing (OB), acting with awareness (AA), describing (DS), and non-judging of inner experience (NJ).

• The Depression, Anxiety, and Stress Scale-21 (DASS; Lovibond & Lovibond, 1995), which provides a non-clinical measure of the severity of symptoms associated with depression (D), anxiety (A), and stress (S).

• A Job Effectiveness Questionnaire (JEQ), which provides a measure of perceived job competency.

After completing the above measures, participants in the experimental condition completed a 30-day mindfulness program. After the experimental group had completed the program (i.e. T2), all participants completed the above self-report measures for a second time. Following the T2 testing period, participants in the control condition completed the 30-day mindfulness program. Once the control group had completed the program (i.e. T3), all participants completed the self-report measures for a third time.

If the intervention was effective in improving well-being and perceived job competency, analyses should reveal an interaction between time and condition such that, from T1 to T2, participants in the experimental condition experienced an increase in scores on the JEQ, the BRS, the positive affect subscale of the PANAS, and all subscales of the FFMQ, as well as a decrease in scores on the PSS, the negative affect subscale of the PANAS, and all subscales of the DASS. Between these two testing periods, participants in the control condition should show no change in scores on any of the measures considered; instead, participants in the control condition should demonstrate the predicted changes during T2 and T3.

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1. Changes Across All Three Time Points

Our first set of analyses will look at the effect of time and condition on self-report scores across all three time points. For these analyses, we will focus exclusively on participants who provided responses to all three surveys and who actively participated in the meditation program.

Demographic Information

Presented below is some basic demographic information for this subset of participants.

Table 1. Frequency-based demographic information (i.e. n) for participants who completed all three surveys.

	Gender		Meditation Exp.		Yoga Exp.		Tai Chi Exp.	Continued Practice
	Male	Female	Yes	No	Yes	No	No	Yes	No
Control	6	14	8	12	4	16	19	NA	NA
Experimental	6	11	6	11	5	12	16	8	9
Note: A ‘Yes’ column is not provided for the Tai Chi Exp. variable because no participants responded ‘yes’ to this question.

Table 2. Demographic information for participants who completed all three surveys.

Condition	n	M	SD	SE	CI
Age
Control	20	49.1500	10.9846	2.4562	5.1409
Experimental	17	53.0000	7.5581	1.8331	3.8860
Weekly Hours Worked
Control	20	51.3000	8.5045	1.9017	3.9802
Experimental	17	48.4118	7.3998	1.7947	3.8046
Meditation During the Program (Min/Week)
Control	20	38.5000	44.4481	9.9389	20.8023
Experimental	17	36.5882	17.4573	4.2340	8.9757
Meditation After the Program (Min/Week)
Control	20	NA	NA	NA	NA
Experimental	17	17.2794	20.3112	4.9262	10.4431

Perceived Stress Scale

Note: Figures in this document depict score distributions that are estimated based on the means and variances of scores that we measured in our sample. For all figures, time of testing (i.e. T1, T2, and/or T3) is displayed on the horizontal axis, scale scores are displayed on the vertical axis, and dots and whiskers represent the sample means and standard errors, respectively. The control group is depicted in orange and the experimental group is depicted in blue.

When averaged across both groups, T3 scores (M_T3 = 36.43, SD_T3 = 7.31) on the PSS were found to be significantly lower than T1 scores (M_T1 = 41.89, SD_T1 = 7.65; p = 0.01). A significant score difference was not observed between T1 and T2 (M_T2 = 38.3, SD_T2 = 9.18; p = 0.14) or T2 and T3 (p = 0.58).

An effect of condition was not observed.

Positive and Negative Affect Schedule

Positive Affect

Scores on this measure were not found to be affected by time or condition.

Negative Affect

When averaged across both groups, both T2 (M_T2 = 21.76, SD_T2 = 8.34) and T3 (M_T3 = 20.38, SD_T3 = 7.12) scores on the PANAS-Negative were found to be significantly lower than T1 scores (M_T1 = 24, SD_T1 = 9.06; p = 0.004 and p = 0.003, respectively). A significant score difference was not observed between T2 and T3 (p = 0.08).

An effect of condition was not observed.

Brief Resilience Scale

Scores on this measure were not found to be affected by time or condition.

Five Facet Mindfulness Questionnaire

Non-Reactivity

Scores on this measure were not found to be affected by time or condition.

Observing

For participants in the experimental condition, both T2 (M_T2 = 13.59, SD_T2 = 2.62) and T3 (M_T3 = 14.12, SD_T3 = 2.91) scores on the FFMQ-Observing were found to be significantly higher than T1 scores (M_T1 = 11.88, SD_T1 = 3.12; p = .001 and p = 0.01, respectively). A significant score difference was not observed between T2 and T3 (p = 0.31).

For participants in the control condition, an effect of time was not observed.

Acting with Awareness

Scores on this measure were not found to be affected by time or condition.

Describing

Scores on this measure were not found to be affected by time or condition.

Non-Judging

Scores on this measure were not found to be affected by time or condition.

Depression, Anxiety, and Stress Scale

Depression

When averaged across both T2 (M_T2 = 6.67, SD_T2 = 6.54) and T3 (M_T3 = 5.61, SD_T3 = 5.34) scores on the DASS-Depression were found to be significantly lower than T1 scores (M_T1 = 10.28, SD_T1 = 10.48; p = 0.02 and p = 0.001, respectively). A significant score difference was not observed between T2 and T3 (p = 0.25).

An effect of condition was not observed.

Anxiety

Scores on this measure were not found to be affected by time or condition.

Stress

When averaged across both groups, T3 scores (M_T3 = 10.33, SD_T3 = 5.5) on the DASS-Stress were found to be significantly lower than T1 scores (M_T1 = 15.78, SD_T1 = 8.81; p = 0.01). A significant score difference was not observed between T1 and T2 (M_T2 = 11.78, SD_T2 = 7.66; p = 0.06) or T2 and T3 (p = 0.69).

An effect of condition was not observed.

Job Effectiveness Questionnaire

Scores on this measure were not found to be affected by time or condition.

Summary of Results

The following results were found to be statistically significant:

• Perceived Stress Scale

  • a decrease in perceived stress from T1 to T3 (p = 0.01)

• Positive and Negative Affect Schedule

  • a reduction in negative affect from T1 to both T2 and T3 (p = 0.004 and p = 0.003, respectively)

• Five Facet Mindfulness Questionnaire

  • an increase in observing abilities from T1 to both T2 and T3 for participants in the experimental condition (p = .001 and p = 0.01, respectively)

• Depression, Anxiety, and Stress Scale

  • a reduction in depression from T1 to both T2 and T3 (p = 0.02 and p = 0.001, respectively)

  • a reduction in stress from T1 to T3 (p = 0.01)

Conclusion

Initial analyses revealed changes in many of the variables considered. Although these changes were all found to occur in the predicted direction (e.g. a decrease in things like stress and depression and an increase in mindful cognition), the majority of them seem to have occurred over time regardless of condition. The only significant condition-related finding was an increase in observing from T1 to both T2 and T3 for participants in the experimental condition but not for those in the control condition. It seems, therefore, that the meditation program enhanced experimental participants’ observing from T1 to T2 and these improvements were maintained through to T3. If the meditation program was, in fact, responsible for such a change though, it is unclear why a similar increase in observing did not occur between T2 and T3 for participants in the control condition. One possibility is that these effects (or lack thereof) were influenced or obscured by small sample sizes (n_Control = 19 and n_Experimental = 17. Small sample sizes could also be responsible for the nearly significant interaction effects and effects of condition that were revealed in these analyses. In particular, the following results were found to be close to significance:

• Perceived Stress Scale

  • an interaction between condition and time with respect to perceived stress (p = 0.05)

• Positive and Negative Affect Schedule

  • an effect of time on positive affect (p = 0.07)

• Five Facet Mindfulness Questionnaire

  • an increase in non-reactivity, acting with awareness, and non-judging from T1 to T3 (p = 0.05, p = 0.07, and p = 0.1, respectively)

  • an effect of condition on non-reactivity (p = 0.06)

• Depression, Anxiety, and Stress Scale

  • a decrease in stress from T1 to T2 (p = 0.06)

  • an effect of condition on anxiety and stress (p = 0.08 and p = 0.1, respectively)

• Job Effectiveness Questionnaire

  • an effect of time on job effectiveness (p = 0.04)

Had we considered a larger sample size, these effects may have been found to be statistically significant. We will assess this possibility through a series of exploratory follow-up analyses looking at the effects of time and condition on self-report scores across T1 and T2. Between T1 and T2, participants in the experimental condition completed the meditation program while participants in the control condition did nothing. The rate of participant drop-out between these two time points was also smaller than between T1 and T3. Consequently, a secondary analysis with a larger sample size focusing on changes exclusively between T1 and T2 may help to clarify which effects can be attributed to the meditation program and which are due primarily to the passage of time.

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2. Changes Across the First Two Time Points

Our second set of analyses will look at the effect of time and condition on self-report scores across the first two time points (i.e. T1 and T2). For these analyses, we will focus on participants who provided responses to the first two surveys and, for the experimental group, those who actively participated in the meditation program.

Demographic Information

Table 3. Frequency-based demographic information (i.e. n) for participants who completed the first two surveys.

	Gender		Meditation Exp.		Yoga Exp.		Tai Chi Exp.
	Male	Female	Yes	No	Yes	No	No
Control	11	28	17	22	13	26	36
Experimental	11	13	11	13	8	16	22
Note: A ‘Yes’ column is not provided for the Tai Chi Exp. variable because no participants responded ‘yes’ to this question.

Table 4. Demographic information for participants who completed the first two surveys.

Condition	n	M	SD	SE	CI
Age
Control	39	48.0000	10.2803	1.6462	3.3325
Experimental	24	50.1667	9.3514	1.9089	3.9488
Weekly Hours Worked
Control	39	50.8590	10.7428	1.7202	3.4824
Experimental	24	49.7083	8.5133	1.7378	3.5949
Meditation During the Program (Min/Week)
Control	39	NA	NA	NA	NA
Experimental	24	37.0625	17.9082	3.6555	7.5620

Perceived Stress Scale

For those in the experimental condition, T2 scores (M_T2 = 35.92, SD_T2 = 7.06) on the PSS were found to be significantly lower than T1 scores (M_T1 = 42.62, SD_T1 = 7.08); t (23) = 5.49, p < .001, d = 1.12.

For participants in the control condition, an effect of time was not observed.

Positive and Negative Affect Schedule

Positive Affect

For those in the experimental condition, T2 scores (M_T2 = 34.21, SD_T2 = 7.99) on the PANAS-Positive were found to be significantly higher than T1 scores (M_T1 = 31.38, SD_T1 = 7.69); Z = -2.51, p = 0.02, r = 0.51.

For participants in the control condition, an effect of time was not observed.

Negative Affect

For those in the experimental condition, T2 scores (M_T2 = 20.5, SD_T2 = 7.49) on the PANAS-Negative were found to be significantly lower than T1 scores (M_T1 = 24.75, SD_T1 = 8.69); Z = 3.61, p < .001, r = 0.74.

For participants in the control condition, an effect of time was not observed.

Brief Resilience Scale

When averaged across both groups, T2 scores (M_T2 = 3.54, SD_T2 = 0.83) on the BRS were found to be significantly higher than T1 scores (M_T1 = 3.39, SD_T1 = 0.77); F (1, 61) = 9.36, p = 0.003, \(\eta^2_{G}\) = 0.01.

An effect of condition was not observed.

Five Facet Mindfulness Questionnaire

Non-Reactivity

For those in the experimental condition, T2 scores (M_T2 = 15.96, SD_T2 = 3.95) on the FFMQ-Non-Reactivity were found to be significantly higher than T1 scores (M_T1 = 13.79, SD_T1 = 3.73); t (23) = -2.66, p = 0.03, d = -0.54.

For participants in the control condition, an effect of time was not observed.

Observing

For those in the experimental condition, T2 scores (M_T2 = 13.75, SD_T2 = 2.71) on the FFMQ-Observing were found to be significantly higher than T1 scores (M_T1 = 11.88, SD_T1 = 3.33); t (23) = -5.96, p < .001, d = -1.22.

For participants in the control condition, an effect of time was not observed.

Acting with Awareness

For those in the experimental condition, T2 scores (M_T2 = 15.62, SD_T2 = 3.21) on the FFMQ-Awareness were found to be significantly higher than T1 scores (M_T1 = 13.46, SD_T1 = 3.13); t (23) = -3.55, p = 0.003, d = -0.73.

For participants in the control condition, an effect of time was not observed.

Describing

Scores on this measure were not found to be affected by time or condition.

Non-Judging

For those in the experimental condition, T2 scores (M_T2 = 17.08, SD_T2 = 3.54) on the FFMQ-Non-Judging were found to be significantly higher than T1 scores (M_T1 = 15.29, SD_T1 = 4.21); t (23) = -3.21, p = 0.01, d = -0.66.

For participants in the control condition, an effect of time was not observed.

Depression, Anxiety, and Stress Scale

Depression

For those in the experimental condition, T2 scores (M_T2 = 5.75, SD_T2 = 5.85) on the DASS-Depression were found to be significantly lower than T1 scores (M_T1 = 10.92, SD_T1 = 11.24); Z = 3.35, p = 0.001, r = 0.68.

For participants in the control condition, an effect of time was not observed.

Anxiety

Scores on this measure were not found to be affected by time or condition.

Stress

For those in the experimental condition, T2 scores (M_T2 = 9.58, SD_T2 = 5.96) on the DASS-Stress were found to be significantly lower than T1 scores (M_T1 = 14.5, SD_T1 = 7.9); t(23) = 4.92, p < .001, d = 1.

For participants in the control condition, an effect of time was not observed.

Job Effectiveness Questionnaire

Scores on this measure were not found to be affected by time or condition.

Percent Change

The following table presents the percent change observed in each variable across time for each condition.

Table 5. Percent change from T1 to T2 for participants in both conditions.

Measure	Experimental Condition (%)	Control Condition (%)
Perceived Stress Scale
	-15.74	-3.06
Positive and Negative Affect Schedule
Positive Affect	9.03	-1.79
Negative Affect	-17.17	-3.52
Brief Resilience Scale
	8.63	2.36
Five Facet Mindfulness Questionnaire
Non-Reactivity	15.71	3.62
Observing	15.79	-2.66
Awareness	16.10	3.83
Describing	2.32	1.43
Non-Judging	11.72	2.12
Depression, Anxiety, and Stress Scale
Depression	-47.33	-14.29
Anxiety	-36.59	-1.63
Stress	-33.91	-7.19
Job Effectiveness Questionnaire
	1.36	-1.12
Note: Positive (negative) values indicate an increase (decrease) over time from T1 to T2.

Summary of Results

The following results were found to be statistically significant:

• Perceived Stress Scale

  • a decrease in perceived stress from T1 to T2 for participants in the experimental condition (p < .001)

• Positive and Negative Affect Schedule

  • an increase in positive affect from T1 to T2 for participants in the experimental condition (p = 0.02)

  • a reduction in negative affect from T1 to T2 for participants in the experimental condition (p < .001)

• Brief Resilience Scale

  • an increase in psychological resilience from T1 to T2 (p = 0.003)

• Five Facet Mindfulness Questionnaire

  • an increase in non-reactivity, observing, acting with awareness, and non-judging from T1 to T2 for participants in the experimental condition (p = 0.03, p < .001, p = 0.003, and p = 0.01, respectively)

• Depression, Anxiety, and Stress Scale

  • a reduction in depression and stress from T1 to T2 for participants in the experimental condition (p = 0.001 and p < .001, respectively)

Conclusion

A second set of analyses provided support for most of the hypotheses made in this study. In particular, participants in the experimental condition reported a decrease in stress (measured by both the PSS and the DASS), negative affect, and depression, as well as an increase in positive affect, non-reactivity, observing, acting with awareness, and non-judgmentalness following the completion of the mindfulness intervention. In contrast, participants in the control condition reported no change from T1 to T2 in any of the variables considered. These results, therefore, suggest that the meditation program was effective in enhancing mindful cognition (measured by the FFMQ) and improving participants’ psychological well-being, though it had no impact on their perceived competency at work (as measured by the JEQ). Another possibility, however, is that participants in the control condition were significantly different at T1 from those in the experimental condition. By this logic, T1 to T2 changes may not have been observed in control participants simply because they were initially low/high in things like stress/positive affect. This next set of analyses will investigate this possibility by assessing between-group differences at T1.

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3. Between-Group Differences During the First Testing Period

Our third set of analyses will look at the effect of condition on T1 scores. Because we are specifically interested in testing an alternate interpretation of the results from the previous section, we will limit the present analysis to the participants included in the previous analysis (i.e. Analysis 2).

Perceived Stress Scale

A significant difference in T1 PSS scores was not observed between the control (M_C = 41.05, SD_C = 7.66) and experimental (M_E = 42.62, SD_E = 7.08) conditions; Z = -0.85, p = 0.4, r = 0.11.

Positive and Negative Affect Schedule

Positive Affect

A significant difference in T1 PANAS-Positive scores was not observed between the control (M_C = 32.87, SD_C = 6.33) and experimental (M_E = 31.38, SD_E = 7.69) conditions; t (61) = 0.84, p = 0.4, d = 0.22.

Negative Affect

A significant difference in T1 PANAS-Negative scores was not observed between the control (M_C = 24.03, SD_C = 8.91) and experimental (M_E = 24.75, SD_E = 8.69) conditions; Z = -0.21, p = 0.84, r = 0.03.

Brief Resilience Scale

A significant difference in T1 BRS scores was not observed between the control (M_C = 3.44, SD_C = 0.76) and experimental (M_E = 3.3, SD_E = 0.81) conditions; t (61) = 0.7, p = 0.49, d = 0.18.

Five Facet Mindfulness Questionnaire

Non-Reactivity

A significant difference in T1 FFMQ-Non-Reactivity scores was not observed between the control (M_C = 14.18, SD_C = 3.6) and experimental (M_E = 13.79, SD_E = 3.73) conditions; t (61) = 0.41, p = 0.68, d = 0.11.

Observing

A significant difference in T1 FFMQ-Observing scores was not observed between the control (M_C = 13.49, SD_C = 3.31) and experimental (M_E = 11.88, SD_E = 3.33) conditions; t (61) = 1.87, p = 0.07, d = 0.49.

Acting with Awareness

Control participants (M_C = 15.38, SD_C = 3.84) scored significantly higher on the FFMQ-Awareness at T1 than did experimental participants (M_E = 13.46, SD_E = 3.13); t (61) = 2.07, p = 0.04, d = 0.54. In fact, control participants’ T1 scores were found to be similar to experimental participants’ T2 scores (M_E = 15.62, SD_E = 3.21); t (61) = -0.26, p = 0.8, d = -0.07.

Describing

A significant difference in T1 FFMQ-Describing scores was not observed between the control (M_C = 17.9, SD_C = 3.63) and experimental (M_E = 17.96, SD_E = 2.49) conditions; Z = 0.09, p = 0.94, r = 0.01.

Non-Judging

A significant difference in T1 FFMQ-Non-Judging scores was not observed between the control (M_C = 16.95, SD_C = 4.72) and experimental (M_E = 15.29, SD_E = 4.21) conditions; t (61) = 1.41, p = 0.16, d = 0.37.

Depression, Anxiety, and Stress Scale

Depression

A significant difference in T1 DASS-Depression scores was not observed between the control (M_C = 7.54, SD_C = 8.24) and experimental (M_E = 10.92, SD_E = 11.24) conditions; Z = -1.04, p = 0.3, r = 0.13.

Anxiety

A significant difference in T1 DASS-Anxiety scores was not observed between the control (M_C = 6.31, SD_C = 8.29) and experimental (M_E = 6.83, SD_E = 6.7) conditions; Z = -0.89, p = 0.38, r = 0.11.

Stress

A significant difference in T1 DASS-Stress scores was not observed between the control (M_C = 14.97, SD_C = 8.78) and experimental (M_E = 14.5, SD_E = 7.9) conditions; Z = -0.04, p = 0.97, r = 0.01.

Job Effectiveness Questionnaire

A significant difference in T1 JEQ scores was not observed between the control (M_C = 5.3, SD_C = 0.65) and experimental (M_E = 5.18, SD_E = 0.62) conditions; Z = 0.45, p = 0.66, r = 0.06.

Summary of Results

The following results were found to be statistically significant:

• Five Facet Mindfulness Questionnaire

  • control participants displayed a greater degree of acting with awareness at T1 than did experimental participants (p = 0.01) and, in fact, displayed levels at T1 that were similar to the levels displayed by the experimental group at T2 (p = 0.8)

Conclusion

This third set of analyses revealed that control participants displayed a level of acting with awareness at T1 that was greater than the level displayed at T1 by those in the experimental condition; in fact, T1 control scores on the FFMQ-Awareness were similar to T2 experimental scores on this measure. This suggests that, for some reason, participants in the experimental condition began the study with a lower level of awareness than those in the control condition. Following the intervention, experimental participants’ level of awareness increased to that of the control condition. We cannot, however, state with certainty that this increase in awareness was due solely to the mindfulness intervention because:

1. there may be some innate between-group difference that both effects trait awareness and moderates how effective the program is in altering this characteristic at a state level, and/or

2. the observed T1-T2 change in experimental group awareness may have been caused by the passage of time, the effects of which were not found to be significant for those in the control condition simply because the control group began the study with a higher degree of awareness.

With respect to the FFMQ-Awareness, therefore, it is unclear if the effects observed in the previous set of analyses are attributable to the mindfulness intervention, the passage of time, or some other unknown factor.

With the exception of the FFMQ-Awareness though, participants in both groups scored similarly at T1 on all of the measures considered. These results, in combination with the results from the previous section, suggest that all participants began at similar levels of stress, affect, etc., and that something occurred between T1 and T2 to drive a change in these variables for participants in the experimental condition but not for those in the control condition. These results, therefore, provide additional support for the efficacy of the mindfulness intervention in improving psychological well-being.

We will now assess this conclusion further through another series of exploratory analyses looking at the effects of time on self-report scores across T2 and T3. If the mindfulness intervention is effective in altering the outcome measures considered in this study, participants in the control condition should have experienced changes between T2 and T3 (following their completion of the mindfulness intervention) that were similar to those observed between T1 and T2 for those in the experimental condition. Note, however, that there is a major caveat to this next analysis, namely that there is no control group with which the control group may be adequately compared to. Although we have T2-T3 data for participants in the experimental condition, experimental participants may have continued to practice the meditations from the mindfulness intervention throughout this period of time and/or their T3 responses may have been influenced by long-term carry-over effects of the program. (Recall, for instance, that the first set of analyses revealed a condition-specific increase in observing across all three time points, indicating that experimental participants may have experienced intervention-related changes that were subsequently maintained following the end of the mindfulness program.) Consequently, the experimental condition will be excluded from the next set of analyses but any results obtained should be interpreted with caution.

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4. Control Changes Across the Last Two Time Points

Our fourth set of analyses will look at the effect of time on control participant self-report scores across the last two time points (i.e. T2 and T3). For these analyses, we will focus on control participants who provided responses to the last two surveys and who actively participated in the meditation program.

Demographic Information

Presented below is some basic demographic information for this subset of participants.

Table 6. Frequency-based demographic information (i.e. n) for control participants who completed the last two surveys.

Gender		Meditation Exp.		Yoga Exp.		Tai Chi Exp.
Male	Female	Yes	No	Yes	No	Yes	No
7	14	9	12	4	17	1	19

Table 7. Demographic information for control participants who completed the last two surveys.

n	M	SD	SE	CI
Age
21	48.5238	11.0843	2.4188	5.0455
Weekly Hours Worked
21	51.7143	8.5038	1.8557	3.8709
Meditation During the Program (Min/Week)
21	40.9524	44.7565	9.7667	20.3729

Perceived Stress Scale

For those in the control condition, T3 scores (M_T3 = 36.57, SD_T3 = 7.82) on the PSS were found to be significantly lower than T2 scores (M_T2 = 39.67, SD_T2 = 10.77); t (20) = 2.3, p = 0.03, d = 0.5.

Positive and Negative Affect Schedule

Positive Affect

For those in the control condition, scores on this measure were not found to be affected by time.

Negative Affect

For those in the control condition, T3 scores (M_T3 = 21.43, SD_T3 = 7.11) on the PANAS-Negative were found to be significantly lower than T2 scores (M_T2 = 23.86, SD_T2 = 9.71); Z = 2.23, p = 0.02, r = 0.49.

Brief Resilience Scale

For those in the control condition, scores on this measure were not found to be affected by time.

Five Facet Mindfulness Questionnaire

Non-Reactivity

For those in the control condition, scores on this measure were not found to be affected by time.

Observing

For those in the control condition, scores on this measure were not found to be affected by time.

Acting with Awareness

For those in the control condition, scores on this measure were not found to be affected by time.

Describing

For those in the control condition, scores on this measure were not found to be affected by time.

Non-Judging

For those in the control condition, T3 scores (M_T3 = 18.05, SD_T3 = 4.49) on the FFMQ-Non-Judging were found to be significantly higher than T2 scores (M_T2 = 15.95, SD_T2 = 5.45); t (19) = -2.43, p = 0.03, d = -0.54.

Depression, Anxiety, and Stress Scale

Depression

For those in the control condition, scores on this measure were not found to be affected by time.

Anxiety

For those in the control condition, scores on this measure were not found to be affected by time.

Stress

For those in the control condition, scores on this measure were not found to be affected by time.

Job Effectiveness Questionnaire

For those in the control condition, T3 scores (M_T3 = 5.47, SD_T3 = 0.86) on the JEQ were found to be significantly higher than T2 scores (M_T2 = 5.17, SD_T2 = 0.97); Z = -2.39, p = 0.01, r = 0.53.

Percent Change

The following table presents the percent change observed in each variable across time.

Table 8. Percent change from T2 to T3 for participants in the control condition.

Measure	Control Condition (%)
Perceived Stress Scale
	-7.80
Positive and Negative Affect Schedule
Positive Affect	5.12
Negative Affect	-10.18
Brief Resilience Scale
	3.58
Five Facet Mindfulness Questionnaire
Non-Reactivity	7.93
Observing	5.47
Awareness	4.56
Describing	-0.29
Non-Judging	13.17
Depression, Anxiety, and Stress Scale
Depression	-25.68
Anxiety	-8.70
Stress	-14.81
Job Effectiveness Questionnaire
	5.81
Note: Positive (negative) values indicate an increase (decrease) over time from T2 to T3.

Summary of Results

The following results were found to be statistically significant with respect to the control group:

• Perceived Stress Scale

  • a decrease in perceived stress from T2 to T3 (p = 0.03)

• Positive and Negative Affect Schedule

  • a reduction in negative affect from T2 to T3 (p = 0.02)

• Five Facet Mindfulness Questionnaire

  • an increase in non-judging from T2 to T3 (p = 0.03

• Job Effectiveness Questionnaire

  • an increase in perceived job effectiveness from T2 to T3 (p = 0.01)

Conclusion

This fourth set of analyses provided some additional support for the conclusion that the mindfulness intervention was effective in improving participants’ well-being. Additionally, the intervention seems to have had a positive effect on control participants’ perceived competency on the job. As previously discussed, however, the results from this set of analyses should be interpreted with caution, as the lack of a comparison group means that we cannot account for factors such as the passage of time or time of assessment. Furthermore, the size of the sample considered here is fairly small. As in the first set of analyses, a small sample size may explain why, compared to the second set of analyses, these fourth tests revealed fewer significant findings. Related to the previous set of analyses, another interesting possibility is that the effectiveness of the mindfulness intervention is moderated by factors measured by the FFMQ-Awareness or by a third variable that also influences trait awareness; this could explain why those in the experimental condition (lower in initial awareness) seem to have been affected more by the program than those in the control condition (higher in initial awareness). Nevertheless, all effects, whether significant or not, were found to occur in the expected direction (i.e. an increase in positive affect, psychological resilience, and mindful cognition, and a decrease in stress, depression, anxiety, and negative affect, over time). In our next set of analyses, we will assess if any of the pre- to post-intervention changes are related to the length of previous meditation experience or the degree of intervention participation.

5. Relationship with Other Variables - All Participants

Our fifth set of analyses will assess the potential relationship between changes in the outcome scores and both level of participation and length of previous meditation experience. We will only include data from participants who actively participated in the meditation program and who completed the appropriate surveys (i.e. the experimental and control participants from Analysis 2 and Analysis 4, respectively).

Correlation

Two-tailed Pearson correlations were used to test for basic relationships between pre- to post-intervention changes in self report scores and (1) years of previous experience and (2) number of minutes per week that participants reported meditating for.

Table 9. Two-tailed Pearson correlations between pre to post-intervention changes in self report scores and both years of previous experience and number of minutes per week spent meditating.

	Previous Experience (yrs)			Program Participation (mins/wk)
Measure	r	n	p	r	n	p
Perceived Stress Scale
	-0.1361	43	1	-0.2855	45	0.6877
Positive and Negative Affect Schedule
Positive Affect	0.2004	43	1	0.0874	45	1
Negative Affect	0.1664	43	1	-0.2241	45	1
Brief Resilience Scale
	-0.1474	43	1	-0.2122	45	1
Five Facet Mindfulness Questionnaire
Non-Reactivity	-0.0978	42	1	-0.0536	44	1
Observing	0.1370	42	1	0.1212	44	1
Awareness	-0.0528	42	1	0.0035	44	1
Describing	-0.0718	42	1	0.1596	44	1
Non-Judging	-0.1649	42	1	0.4067	44	0.08
Depression, Anxiety, and Stress Scale
Depression	0.1284	42	1	-0.2163	44	1
Anxiety	0.0847	42	1	-0.2026	44	1
Stress	-0.0276	42	1	-0.1507	44	1
Job Effectiveness Questionnaire
	-0.0074	42	1	0.1396	44	1
Note: Changes were calculated as post-test minus pre-test. For each set of comparisons (i.e. changes/previous experience and changes/program participation), a Holm-Bonferroni adjustment has been applied to correct the family-wise error rate. Values in bold are significant at the p < .05 level.

None of the pre to post-intervention changes for either condition were found to be significantly correlated with years of previous experience or with minutes per week spent meditating (all p’s > .05).

Moderation

Moderation was tested via the method described in Case 2 of Judd et al. (2001). According to this method, moderation in a within-subject design can be estimated by performing a regression analysis with T1-T2 changes as the dependent variable and the suspected moderator as the independent variable. In this case, a significant independent variable coefficient indicates moderation; furthermore, if the moderator value is centered, the estimated intercept corresponds to the average treatment effect.

Perceived Stress Scale

1. Previous Experience

Previous experience was found to explain 1.85% of the change in PSS scores; R² = 0.02, F(1, 41 ) = 0.77, p = 0.38. Length of previous experience is not a significant moderator of PSS change; \(\beta\) = -0.25, t = -0.88, p = 0.38.

2. Program Participation

Program participation was found to explain 8.15% of the change in PSS scores; R² = 0.08, F(1, 43 ) = 3.82, p = 0.06. Time spent meditating is not a significant moderator of PSS change; \(\beta\) = -0.05, t = -1.95, p = 0.06.

Positive and Negative Affect Schedule

Positive Affect

1. Previous Experience

Previous experience was found to explain 4.02% of the change in PANAS-Positive scores; R² = 0.04, F(1, 41 ) = 1.72, p = 0.2. Length of previous experience is not a significant moderator of PANAS-Positive change; \(\beta\) = 0.28, t = 1.31, p = 0.2.

2. Program Participation

Program participation was found to explain 0.76% of the change in PANAS-Positive scores; R² = 0.01, F(1, 43 ) = 0.33, p = 0.57. Time spent meditating is not a significant moderator of PANAS-Positive change; \(\beta\) = 0.01, t = 0.58, p = 0.57.

Negative Affect

1. Previous Experience

Previous experience was found to explain 2.77% of the change in PANAS-Negative scores; R² = 0.03, F(1, 41 ) = 1.17, p = 0.29. Length of previous experience is not a significant moderator of PANAS-Negative change; \(\beta\) = 0.23, t = 1.08, p = 0.29.

2. Program Participation

Program participation was found to explain 5.02% of the change in PANAS-Negative scores; R² = 0.05, F(1, 43 ) = 2.27, p = 0.14. Time spent meditating is not a significant moderator of PANAS-Negative change; \(\beta\) = -0.03, t = -1.51, p = 0.14.

Brief Resilience Scale

1. Previous Experience

Previous experience was found to explain 2.17% of the change in BRS scores; R² = 0.02, F(1, 41 ) = 0.91, p = 0.35. Length of previous experience is not a significant moderator of BRS change; \(\beta\) = -0.02, t = -0.95, p = 0.35.

2. Program Participation

Program participation was found to explain 4.5% of the change in BRS scores; R² = 0.05, F(1, 43 ) = 2.03, p = 0.16. Time spent meditating is not a significant moderator of BRS change; \(\beta\) = 0, t = -1.42, p = 0.16.

Five Facet Mindfulness Questionnaire

Non-Reactivity

1. Previous Experience

Previous experience was found to explain 0.96% of the change in FFMQ-Non-Reactivity scores; R² = 0.01, F(1, 40 ) = 0.39, p = 0.54. Length of previous experience is not a significant moderator of FFMQ-Non-Reactivity change; \(\beta\) = -0.1, t = -0.62, p = 0.54.

2. Program Participation

Program participation was found to explain 0.29% of the change in FFMQ-Non-Reactivity scores; R² = 0, F(1, 42 ) = 0.12, p = 0.73. Time spent meditating is not a significant moderator of FFMQ-Non-Reactivity change; \(\beta\) = -0.01, t = -0.35, p = 0.73.

Observing

1. Previous Experience

Previous experience was found to explain 1.88% of the change in FFMQ-Observing scores; R² = 0.02, F(1, 40 ) = 0.76, p = 0.39. Length of previous experience is not a significant moderator of FFMQ-Observing change; \(\beta\) = 0.09, t = 0.87, p = 0.39.

2. Program Participation

Program participation was found to explain 1.47% of the change in FFMQ-Observing scores; R² = 0.01, F(1, 42 ) = 0.63, p = 0.43. Time spent meditating is not a significant moderator of FFMQ-Observing change; \(\beta\) = 0.01, t = 0.79, p = 0.43.

Acting with Awareness

1. Previous Experience

Previous experience was found to explain 0.28% of the change in FFMQ-Awareness scores; R² = 0, F(1, 40 ) = 0.11, p = 0.74. Length of previous experience is not a significant moderator of FFMQ-Awareness change; \(\beta\) = -0.05, t = -0.33, p = 0.74.

2. Program Participation

Program participation was found to explain 0% of the change in FFMQ-Awareness scores; R² = 0, F(1, 42 ) = 0, p = 0.98. Time spent meditating is not a significant moderator of FFMQ-Awareness change; \(\beta\) = 0, t = 0.02, p = 0.98.

Describing

1. Previous Experience

Previous experience was found to explain 0.51% of the change in FFMQ-Describing scores; R² = 0.01, F(1, 40 ) = 0.21, p = 0.65. Length of previous experience is not a significant moderator of FFMQ-Describing change; \(\beta\) = -0.06, t = -0.46, p = 0.65.

2. Program Participation

Program participation was found to explain 2.55% of the change in FFMQ-Describing scores; R² = 0.03, F(1, 42 ) = 1.1, p = 0.3. Time spent meditating is not a significant moderator of FFMQ-Describing change; \(\beta\) = 0.01, t = 1.05, p = 0.3.

Non-Judging

1. Previous Experience

Previous experience was found to explain 2.72% of the change in FFMQ-Non-Judging scores; R² = 0.03, F(1, 40 ) = 1.12, p = 0.3. Length of previous experience is not a significant moderator of FFMQ-Non-Judging change; \(\beta\) = -0.16, t = -1.06, p = 0.3.

2. Program Participation

Program participation was found to explain 16.54% of the change in FFMQ-Non-Judging scores; R² = 0.17, F(1, 42 ) = 8.32, p = 0.01. Time spent meditating is a significant moderator of FFMQ-Non-Judging change, meaning that participants who meditated more demonstrated more positive change over time; \(\beta\) = 0.04, t = 2.88, p = 0.01. This relationship is plotted below.

Depression, Anxiety, and Stress Scale

Depression

1. Previous Experience

Previous experience was found to explain 1.65% of the change in DASS-Depression scores; R² = 0.02, F(1, 40 ) = 0.67, p = 0.42. Length of previous experience is not a significant moderator of DASS-Depression change; \(\beta\) = 0.26, t = 0.82, p = 0.42.

2. Program Participation

Program participation was found to explain 4.68% of the change in DASS-Depression scores; R² = 0.05, F(1, 42 ) = 2.06, p = 0.16. Time spent meditating is not a significant moderator of DASS-Depression change; \(\beta\) = -0.04, t = -1.44, p = 0.16.

Anxiety

1. Previous Experience

Previous experience was found to explain 0.72% of the change in DASS-Anxiety scores; R² = 0.01, F(1, 40 ) = 0.29, p = 0.59. Length of previous experience is not a significant moderator of DASS-Anxiety change; \(\beta\) = 0.15, t = 0.54, p = 0.59.

2. Program Participation

Program participation was found to explain 4.1% of the change in DASS-Anxiety scores; R² = 0.04, F(1, 42 ) = 1.8, p = 0.19. Time spent meditating is not a significant moderator of DASS-Anxiety change; \(\beta\) = -0.04, t = -1.34, p = 0.19.

Stress

1. Previous Experience

Previous experience was found to explain 0.08% of the change in DASS-Stress scores; R² = 0, F(1, 40 ) = 0.03, p = 0.86. Length of previous experience is not a significant moderator of DASS-Stress change; \(\beta\) = -0.04, t = -0.17, p = 0.86.

2. Program Participation

Program participation was found to explain 2.27% of the change in DASS-Stress scores; R² = 0.02, F(1, 42 ) = 0.98, p = 0.33. Time spent meditating is not a significant moderator of DASS-Stress change; \(\beta\) = -0.03, t = -0.99, p = 0.33.

Job Effectiveness Questionnaire

1. Previous Experience

Previous experience was found to explain 0.01% of the change in JEQ scores; R² = 0, F(1, 40 ) = 0, p = 0.96. Length of previous experience is not a significant moderator of JEQ change; \(\beta\) = 0, t = -0.05, p = 0.96.

2. Program Participation

Program participation was found to explain 1.95% of the change in JEQ scores; R² = 0.02, F(1, 42 ) = 0.84, p = 0.37. Time spent meditating is not a significant moderator of JEQ change; \(\beta\) = 0, t = 0.91, p = 0.37.

Summary of Results

The following results were found to be statistically significant:

• Five Facet Mindfulness Questionnaire

  • non-judging changes were moderated by program participation (p = 0.01)

Conclusion

Correlational analyses suggest that intervention-related changes were unrelated to both the length of previous experience and the degree to which an individual participated in the program. This conclusion is generally supported by moderation analyses, though changes in non-judging were found to be moderated by the degree of program participation, such that more participation led to greater change across time. It’s important to note, however, that this relationship may have been unduly influenced by two exceptional participants who reported meditating for 100+ minutes per week. In the next set of analyses, therefore, we will repeat the previous analyses after removing outliers.

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6. Relationship with Other Variables - Outliers Removed

Our sixth set of analyses will assess the potential relationship between changes in the outcome scores and both level of participation and length of previous meditation experience for those deemed to be non-outliers.

Outlier Identification

Before we begin, we will identify participants with extreme experience and participation values. These participants will be excluded from the analyses in this section.

1. Previous Experience

The outlier values correspond to participants 66, 87, and 14, who reported 0.75 years of meditation experience; 53, 71, 88, and 29, who reported 2 years of meditation experience; 70, who reported 5 years of meditation experience; 61, who reported 10 years of meditation experience; and 82, who reported 20 years of meditation experience.

2. Program Participation

The outlier values correspond to participants 14 and 42. These participants reported meditating for 180 and 105 minutes per week, respectively.

Correlation

As before, two-tailed Pearson correlations were used to test for basic relationships between pre- to post-intervention changes in self report scores and (1) years of previous experience and (2) number of minutes per week that participants reported meditating for.

Table 10. Two-tailed Pearson correlations between pre to post-intervention changes in self report scores and both years of previous experience and number of minutes per week spent meditating.

	Previous Experience (yrs)			Program Participation (mins/wk)
Measure	r	n	p	r	n	p
Perceived Stress Scale
	-0.0507	33	1	-0.2719	43	0.7004
Positive and Negative Affect Schedule
Positive Affect	0.0146	33	1	0.0610	43	1
Negative Affect	0.0165	33	1	-0.1957	43	1
Brief Resilience Scale
	-0.1688	33	1	0.0733	43	1
Five Facet Mindfulness Questionnaire
Non-Reactivity	-0.0325	33	1	0.0115	42	1
Observing	-0.0201	33	1	0.2118	42	1
Awareness	0.0126	33	1	0.1066	42	1
Describing	-0.0139	33	1	0.2516	42	0.756
Non-Judging	0.0625	33	1	0.3512	42	0.2484
Depression, Anxiety, and Stress Scale
Depression	-0.1939	33	1	-0.2635	42	0.7339
Anxiety	-0.0004	33	1	-0.3836	42	0.1458
Stress	-0.0172	33	1	-0.4279	42	0.0611
Job Effectiveness Questionnaire
	0.2076	33	1	0.2862	42	0.6609
Note: Changes were calculated as post-test minus pre-test. For each set of comparisons (i.e. changes/previous experience and changes/program participation), a Holm-Bonferroni adjustment has been applied to correct the family-wise error rate. Values in bold are significant at the p < .05 level.

None of the pre to post-intervention changes for either condition were found to be significantly correlated with years of previous experience or with minutes per week spent meditating (all p’s > .05).

Moderation

As before, moderation was tested by performing regression analyses with T1-T2 changes as the dependent variables and the suspected moderators as the independent variables.

Perceived Stress Scale

1. Previous Experience

After removing outliers, previous experience was found to explain 0.26% of the change in PSS scores; R² = 0, F(1, 31 ) = 0.08, p = 0.78. Length of previous experience, therefore, remains a non-significant moderator of PSS change; \(\beta\) = -3.77, t = -0.28, p = 0.78.

2. Program Participation

After removing outliers, program participation was found to explain 7.39% of the change in PSS scores; R² = 0.07, F(1, 41 ) = 3.27, p = 0.08. Time spent meditating, therefore, remains a non-significant moderator of PSS change; \(\beta\) = -0.07, t = -1.81, p = 0.08.

Positive and Negative Affect Schedule

Positive Affect

1. Previous Experience

After removing outliers, previous experience was found to explain 0.02% of the change in PANAS-Positive scores; R² = 0, F(1, 31 ) = 0.01, p = 0.94. Length of previous experience, therefore, remains a non-significant moderator of PANAS-Positive change; \(\beta\) = 0.8, t = 0.08, p = 0.94.

2. Program Participation

After removing outliers, program participation was found to explain 0.37% of the change in PANAS-Positive scores; R² = 0, F(1, 41 ) = 0.15, p = 0.7. Time spent meditating, therefore, remains a non-significant moderator of PANAS-Positive change; \(\beta\) = 0.01, t = 0.39, p = 0.7.

Negative Affect

1. Previous Experience

After removing outliers, previous experience was found to explain 0.03% of the change in PANAS-Negative scores; R² = 0, F(1, 31 ) = 0.01, p = 0.93. Length of previous experience, therefore, remains a non-significant moderator of PANAS-Negative change; \(\beta\) = 0.77, t = 0.09, p = 0.93.

2. Program Participation

After removing outliers, program participation was found to explain 3.83% of the change in PANAS-Negative scores; R² = 0.04, F(1, 41 ) = 1.63, p = 0.21. Time spent meditating, therefore, remains a non-significant moderator of PANAS-Negative change; \(\beta\) = -0.04, t = -1.28, p = 0.21.

Brief Resilience Scale

1. Previous Experience

After removing outliers, previous experience was found to explain 2.85% of the change in BRS scores; R² = 0.03, F(1, 31 ) = 0.91, p = 0.35. Length of previous experience, therefore, remains a non-significant moderator of BRS change; \(\beta\) = -0.98, t = -0.95, p = 0.35.

2. Program Participation

After removing outliers, program participation was found to explain 0.54% of the change in BRS scores; R² = 0.01, F(1, 41 ) = 0.22, p = 0.64. Time spent meditating, therefore, remains a non-significant moderator of BRS change; \(\beta\) = 0, t = 0.47, p = 0.64.

Five Facet Mindfulness Questionnaire

Non-Reactivity

1. Previous Experience

After removing outliers, previous experience was found to explain 0.11% of the change in FFMQ-Non-Reactivity scores; R² = 0, F(1, 31 ) = 0.03, p = 0.86. Length of previous experience, therefore, remains a non-significant moderator of FFMQ-Non-Reactivity change; \(\beta\) = -1.31, t = -0.18, p = 0.86.

2. Program Participation

After removing outliers, program participation was found to explain 0.01% of the change in FFMQ-Non-Reactivity scores; R² = 0, F(1, 40 ) = 0.01, p = 0.94. Time spent meditating, therefore, remains a non-significant moderator of FFMQ-Non-Reactivity change; \(\beta\) = 0, t = 0.07, p = 0.94.

Observing

1. Previous Experience

After removing outliers, previous experience was found to explain 0.04% of the change in FFMQ-Observing scores; R² = 0, F(1, 31 ) = 0.01, p = 0.91. Length of previous experience, therefore, remains a non-significant moderator of FFMQ-Observing change; \(\beta\) = -0.57, t = -0.11, p = 0.91.

2. Program Participation

After removing outliers, program participation was found to explain 4.49% of the change in FFMQ-Observing scores; R² = 0.04, F(1, 40 ) = 1.88, p = 0.18. Time spent meditating, therefore, remains a non-significant moderator of FFMQ-Observing change; \(\beta\) = 0.02, t = 1.37, p = 0.18.

Acting with Awareness

1. Previous Experience

After removing outliers, previous experience was found to explain 0.02% of the change in FFMQ-Awareness scores; R² = 0, F(1, 31 ) = 0, p = 0.94. Length of previous experience, therefore, remains a non-significant moderator of FFMQ-Awareness change; \(\beta\) = 0.49, t = 0.07, p = 0.94.

2. Program Participation

After removing outliers, program participation was found to explain 1.14% of the change in FFMQ-Awareness scores; R² = 0.01, F(1, 40 ) = 0.46, p = 0.5. Time spent meditating, therefore, remains a non-significant moderator of FFMQ-Awareness change; \(\beta\) = 0.02, t = 0.68, p = 0.5.

Describing

1. Previous Experience

After removing outliers, previous experience was found to explain 0.02% of the change in FFMQ-Describing scores; R² = 0, F(1, 31 ) = 0.01, p = 0.94. Length of previous experience, therefore, remains a non-significant moderator of FFMQ-Describing change; \(\beta\) = -0.43, t = -0.08, p = 0.94.

2. Program Participation

After removing outliers, program participation was found to explain 6.33% of the change in FFMQ-Describing scores; R² = 0.06, F(1, 40 ) = 2.7, p = 0.11. Time spent meditating, therefore, remains a non-significant moderator of FFMQ-Describing change; \(\beta\) = 0.03, t = 1.64, p = 0.11.

Non-Judging

1. Previous Experience

After removing outliers, previous experience was found to explain 0.39% of the change in FFMQ-Non-Judging scores; R² = 0, F(1, 31 ) = 0.12, p = 0.73. Length of previous experience, therefore, remains a non-significant moderator of FFMQ-Non-Judging change; \(\beta\) = 2.28, t = 0.35, p = 0.73.

2. Program Participation

After removing outliers, program participation was found to explain 12.33% of the change in FFMQ-Non-Judging scores; R² = 0.12, F(1, 40 ) = 5.63, p = 0.02. Time spent meditating, therefore, remains a significant moderator of FFMQ-Non-Judging change, meaning that participants who meditated more demonstrated more positive change over time; \(\beta\) = 0.05, t = 2.37, p = 0.02. This relationship is plotted below.

Depression, Anxiety, and Stress Scale

Depression

1. Previous Experience

After removing outliers, previous experience was found to explain 3.76% of the change in DASS-Depression scores; R² = 0.04, F(1, 31 ) = 1.21, p = 0.28. Length of previous experience, therefore, remains a non-significant moderator of DASS-Depression change; \(\beta\) = -15.2, t = -1.1, p = 0.28.

2. Program Participation

After removing outliers, program participation was found to explain 6.94% of the change in DASS-Depression scores; R² = 0.07, F(1, 40 ) = 2.99, p = 0.09. Time spent meditating, therefore, remains a non-significant moderator of DASS-Depression change; \(\beta\) = -0.08, t = -1.73, p = 0.09.

Anxiety

1. Previous Experience

After removing outliers, previous experience was found to explain 0% of the change in DASS-Anxiety scores; R² = 0, F(1, 31 ) = 0, p = 1. Length of previous experience, therefore, remains a non-significant moderator of DASS-Anxiety change; \(\beta\) = -0.03, t = 0, p = 1.

2. Program Participation

After removing outliers, program participation was found to explain 14.72% of the change in DASS-Anxiety scores; R² = 0.15, F(1, 40 ) = 6.9, p = 0.01. Time spent meditating, therefore, was found to be a significant moderator of DASS-Anxiety change, meaning that participants who meditated more demonstrated more negative change over time; \(\beta\) = -0.1, t = -2.63, p = 0.01. This relationship is plotted blow.

For comparison’s-sake, this relationship with all participants included is plotted below.

Stress

1. Previous Experience

After removing outliers, previous experience was found to explain 0.03% of the change in DASS-Stress scores; R² = 0, F(1, 31 ) = 0.01, p = 0.92. Length of previous experience, therefore, remains a non-significant moderator of DASS-Stress change; \(\beta\) = -1.1, t = -0.1, p = 0.92.

2. Program Participation

After removing outliers, program participation was found to explain 18.31% of the change in DASS-Stress scores; R² = 0.18, F(1, 40 ) = 8.97, p = 0.005. Time spent meditating, therefore, was found to be a significant moderator of DASS-Stress change, meaning that participants who meditated more demonstrated more negative change over time; \(\beta\) = -0.1, t = -2.99, p = 0.005.

For comparison’s-sake, this relationship with all participants included is plotted below.

Job Effectiveness Questionnaire

1. Previous Experience

After removing outliers, previous experience was found to explain 4.31% of the change in JEQ scores; R² = 0.04, F(1, 31 ) = 1.4, p = 0.25. Length of previous experience, therefore, remains a non-significant moderator of JEQ change; \(\beta\) = 1.43, t = 1.18, p = 0.25.

2. Program Participation

After removing outliers, program participation was found to explain 8.19% of the change in JEQ scores; R² = 0.08, F(1, 40 ) = 3.57, p = 0.07. Time spent meditating, therefore, remains a non-significant moderator of JEQ change; \(\beta\) = 0.01, t = 1.89, p = 0.07.

Summary of Results

The following results were found to be statistically significant:

• Five Facet Mindfulness Questionnaire

  • non-judging changes were moderated by time spent meditating (p = 0.02)

• Depression, Anxiety, and Stress Scale

  • anxiety changes were moderated by time spent meditating (p = 0.01)

  • stress changes were moderated by time spent meditating (p = 0.005)

Conclusion

As before, correlation analyses suggest that intervention-related changes were unrelated to both the length of previous experience and the degree to which an individual participated in the program. This conclusion is partially supported by moderation analyses, which suggest that length of previous meditation experience is not a significant moderator of the changes that were observed throughout the program. The removal of outliers, however, revealed that time spent meditating was a significant moderator of non-judging and the prevalence of symptoms associated with anxiety and stress. As the inclusion of outlier values initially resulted in smaller slopes and non-significant relationships between time spent meditating and anxiety and stress, it is possible that changes on these measures are tempered by unusually high levels of participation; moderate levels of participation, however, seem to be positively related to decreases in anxiety and stress over time. Increases in non-judging, on the other hand, seem to be positively related to all degrees of participation, as the relationship between these variables was significant with and without outliers. Our seventh and final set of analyses will assess the pre- to post-intervention changes that were observed within the context of the general population. In particular, we will compare participants’ self-report scores with norming data for each measure.

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7. Comparison Between Participants and Norming Data

In this final set of analyses, we will compare participants’ immediate pre- and immediate post-intervention scores with norming data for each measure. Note that, for participants in the experimental condition, “immediate pre” refers to T1 and “immediate post” refers to T2; for those in the control condition, “immediate pre” and “immediate post” refer to T2 and T3, respectively. We will only include data from participants who actively participated in the meditation program and who completed the appropriate surveys (i.e. the participants from Analysis 5).

Because the JEQ was designed specifically for this study, norming data is not available for this scale and it will be excluded from this analysis. With respect to the other scales, norming data was obtained from the following sources:

• The Perceived Stress Scale

• Psychological stress in a probability sample of the United States (Cohen & Williamson, 1988)

• The norming sample, obtained via region-based stratification, is comprised of US residents aged 18 and older.

• Note that the version of the PSS used in this study was the PSS-14.

• The Positive and Negative Affect Schedule

• Development and validation of brief measures of positive and negative affect (Watson et al., 1988)

• The norming sample is comprised of undergraduate students and employees from an American university. Watson et al., (1988) suggest that this sample can be reliably generalized to an adult population.

• In our study, participants were asked to consider how they felt during the past month; therefore, we will use the norms associated with the “past few weeks” instructions.

• The Brief Resilience Scale

  • The foundations of resilience: What are the critical resources for bouncing back from stress? (Smith et al., 2013)

  • Note that, as suggested by Smith et al. (2013, p. 177), we will use the combined sample mean and standard deviation. This combined sample is comprised of American college students, healthy adult women, women with fibromyalgia, cardiac patients, and firefighters.

• The Five Facet Mindfulness Questionnaire

  • Psychometric properties of the five facet mindfulness questionnaire in depressed adults and development of a short form (Bohlmeijer et al., 2011)

  • The norming sample is comprised of Dutch individuals with clinical (but not severe) symptoms of depression and anxiety. The majority of the individuals in this sample were educated women.

  • We will compare our participants with the data collected during the pre-intervention phase of the norming study.

• The Depression, Anxiety, and Stress Scale-21

  • Psychometric evaluation and normative data for the depression, anxiety, and stress scales-21 (DASS-21) in a nonclinical sample of U.S. adults (Sinclair et al., 2012)

  • The norming sample, obtained via stratification sampling, was constructed to be representative of the American population.

Table 11. Norming values to be compared with pre- and post-intervention self-report scores .

Source	Measure	n	M	SD
Perceived Stress Scale
Cohen & Williamson, 1988		2387	19.62	7.49
Positive and Negative Affect Schedule
Watson et al., 1988	Positive Affect	586	32.00	7.00
	Negative Affect	586	19.50	7.00
Brief Resilience Scale
Smith et al., 2013		844	3.70	0.68
Five Facet Mindfulness Questionnaire
Bohlmeijer et al., 2011	Non-Reactivity	376	13.47	3.07
	Observing	376	13.86	3.21
	Awareness	376	13.19	3.32
	Describing	376	16.28	3.91
	Non-Judging	376	14.09	3.63
Depression, Anxiety, and Stress Scale
Sinclair et al., 2012	Depression	499	5.70	8.20
	Anxiety	499	3.99	6.27
	Stress	499	8.12	7.62

Each norming mean will be compared against two other means: the pre-test mean and the post-test mean. For each set of two-way comparisons, therefore, a Holm-Bonferroni adjustment will be applied to correct the family-wise error rate.

Table 12. Comparisons between norming values and self-report scores.

	Pre-Intervention						Post-Intervention
Measure	M	SD	t	df	p	d	M	SD	t	df	p	d
Perceived Stress Scale
	41.24	9.01	-16.00	45.15	0	-2.41	36.22	7.35	-15.01	45.74	0	-2.26
Positive and Negative Affect Schedule
Positive Affect	31.49	7.08	0.47	50.83	0.6426	0.07	33.76	6.99	-1.62	51.01	0.2214	-0.25
Negative Affect	24.33	9.09	-3.49	48.09	0.0021	-0.54	20.93	7.25	-1.28	50.51	0.206	-0.20
Brief Resilience Scale
	3.41	0.83	2.26	47.18	0.0571	0.35	3.63	0.76	0.64	47.85	0.524	0.10
Five Facet Mindfulness Questionnaire
Non-Reactivity	14.13	3.93	-1.09	50.61	0.2801	-0.17	15.82	3.60	-4.15	50.57	0.0003	-0.66
Observing	12.29	3.29	3.04	54.54	0.0073	0.48	13.64	2.87	0.48	56.37	0.6311	0.08
Awareness	14.33	4.05	-1.82	51.34	0.074	-0.29	15.82	3.29	-5.00	53.74	0	-0.80
Describing	17.60	3.65	-2.28	56.82	0.0266	-0.36	17.86	3.74	-2.65	54.61	0.0213	-0.42
Non-Judging	15.62	4.72	-2.11	50.43	0.0402	-0.33	17.52	3.98	-5.46	51.73	0	-0.87
Depression, Anxiety, and Stress Scale
Depression	9.47	9.77	-2.51	49.75	0.031	-0.39	5.64	5.46	0.07	61.59	0.9439	0.01
Anxiety	7.16	7.53	-2.74	49.66	0.0171	-0.43	5.23	5.00	-1.54	55.67	0.1295	-0.24
Stress	14.22	8.05	-4.89	51.37	0	-0.76	10.45	6.04	-2.40	55.84	0.0197	-0.38
Note: For the post-intervention FFMQ and DASS scales, n = 44; for all other measures, n = 45.

Compared to the norming populations considered, participants began the study with significantly higher scores on the PSS; PANAS-Negative; FFMQ-Describing and Non-Judging; and DASS-Depression, Anxiety, and Stress. Participants also began the study with significantly lower scores on the FFMQ-Observing. Following the completion of the mindfulness intervention, participants were no longer significantly different from the norming populations with respect to the PANAS-Negative, FFMQ-Observing, and the depression and anxiety subscales of the DASS, though they remained significantly higher on the PSS and DASS-Stress. Compared to the norming population, participants also ended the study with significantly higher scores on all subscales of the FFMQ but the FFMQ-Observing.

Conclusion

A comparison between norming data and self-report scores indicated that participants were initially experiencing higher levels of perceived stress and negative affect than is present in the general population. Additionally, participants began the study with relatively severe levels of symptoms associated with depression, anxiety, and stress. Compared to a norming population with symptoms of depression and anxiety, participants also initially had lower levels of observing and similar levels of all other mindfulness facets. Throughout the intervention, participants experienced significant increases in aspects related to mindful cognition that ultimately resulted in higher levels of almost all aspects of mindfulness compared to the symptomatic norming population. Participants also experienced significant decreases in stress, as measured by the PSS and DASS, yet these decreases did not lower participant PSS or DASS-Stress scores to the level of scores reported by the norming samples. Reductions in negative affect, depression, and anxiety did, however, bring their post-intervention PANAS-Negative, DASS-Depression, and DASS-Anxiety scores to be within the typical range.

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Overall Conclusions

For experimental participants, the completion of the mindfulness intervention was associated with a decrease in stress, negative affect, and depression, as well as an increase in positive affect, non-reactivity, observing, acting with awareness, and non-judging; additionally, control participants experienced a decrease in stress and negative affect and an increase in non-judging and perceived job effectiveness following the program. These changes failed to decrease participants’ level of stress to levels experienced by the general population. Nevertheless, significant changes in both groups were observed, suggesting that the intervention was effective in enhancing participants’ mindfulness and improving their psychological well-being. Based on correlation and moderation analyses, most improvements seem to have been unrelated to the amount of program engagement (i.e. the amount of time spent meditating throughout the 30-day program) and length of previous meditation experience. It is, however, important to note that sample sizes in both groups were relatively small due to participant drop-out throughout the study. Consequently, though the significant findings and general trends within the data are promising, these results should be interpreted with caution and future work should consider ways in which drop-out can be minimized or mitigated.