The Attention Dataset

   

Please double check this data table below to make sure I have the same data with you.

   

ID ExecutiveNetworks Depression Anxiety Stress ADHD
SADP01 149.55 18 14 18 35
SADP05 187.46 23 25 26 56
SADP09 125.05 31 28 41 60
SADP11 124.16 22 16 27 62
SADP13 182.02 40 38 47 63
SADP14 218.83 20 28 26 49
SADP15 152.98 14 15 14 48
SADP18 179.28 14 14 20 54
SADP25 116.82 42 18 27 36
SADP27 216.76 48 44 42 53
SADP29 287.74 25 28 31 57
SADP30 170.71 19 16 15 36
SADP36 78.94 15 19 21 40
SADP37 216.64 18 18 22 31
SADP40 78.42 14 14 14 36
SADP42 160.49 34 25 29 38
SADP43 136.10 14 16 16 36
SADP44 363.52 23 46 51 73
SADP45 242.28 33 34 45 68
SADP46 88.30 11 15 18 53
SADP47 146.93 9 7 11 67
SADP49 266.71 18 28 17 58
SADP50 102.96 17 24 22 70

     

Mediation Model:

IV = Depression

Mediator = Anxiety

DV = Executive Network

     

Total effect - Effect of IV on DV

## 
## Call:
## lm(formula = ExecutiveNetworks ~ Depression, data = attention)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -86.978 -54.941  -7.008  34.373 189.450 
## 
## Coefficients:
##             Estimate Std. Error t value Pr(>|t|)    
## (Intercept)  138.082     35.623   3.876 0.000873 ***
## Depression     1.565      1.430   1.094 0.286260    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 70.44 on 21 degrees of freedom
## Multiple R-squared:  0.05394,    Adjusted R-squared:  0.008887 
## F-statistic: 1.197 on 1 and 21 DF,  p-value: 0.2863

   

There is NO SIGNIFICANT effect of IV (Depression) on DV (Executive Networks) at alpha = 0.05

     

Effect of IV on Mediator

## 
## Call:
## lm(formula = Anxiety ~ Depression, data = attention)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -17.5741  -4.0218  -0.4517   3.9960  22.7590 
## 
## Coefficients:
##             Estimate Std. Error t value Pr(>|t|)    
## (Intercept)   8.3115     3.8896   2.137 0.044538 *  
## Depression    0.6491     0.1561   4.157 0.000446 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 7.692 on 21 degrees of freedom
## Multiple R-squared:  0.4515, Adjusted R-squared:  0.4253 
## F-statistic: 17.28 on 1 and 21 DF,  p-value: 0.000446

   

There is a SIGNIFICANT EFFECT of IV (Depression) on Mediator (Anxiety), p < 0.0001.

     

Effect of mediator on DV

## 
## Call:
## lm(formula = ExecutiveNetworks ~ Depression + Anxiety, data = attention)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -91.740 -34.163   6.195  36.884  88.217 
## 
## Coefficients:
##             Estimate Std. Error t value Pr(>|t|)    
## (Intercept)   84.469     28.592   2.954 0.007841 ** 
## Depression    -2.622      1.404  -1.867 0.076597 .  
## Anxiety        6.451      1.454   4.437 0.000253 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 51.24 on 20 degrees of freedom
## Multiple R-squared:  0.5232, Adjusted R-squared:  0.4756 
## F-statistic: 10.98 on 2 and 20 DF,  p-value: 0.0006067

   

There is a SIGNIFICANT EFFECT of Mediator (Anxiety) on DV (Executive Networks)

     

Mediation Model with Booststrap Technique (showing result with confident interval)

## 
## Causal Mediation Analysis 
## 
## Nonparametric Bootstrap Confidence Intervals with the Percentile Method
## 
##                Estimate 95% CI Lower 95% CI Upper p-value  
## ACME              4.187        1.151         7.46   0.013 *
## ADE              -2.622       -5.163         0.76   0.097 .
## Total Effect      1.565       -0.496         4.37   0.116  
## Prop. Mediated    2.676       -7.449        16.55   0.129  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Sample Size Used: 23 
## 
## 
## Simulations: 10000

     

FULL MEDIATTION EFFECT EXIST!! ANXIETY DOES APPEAR TO BE THE THE MEDIATOR BETWEEN DEPRESSION AND ANXIETY

Based on the Causal Mediation Analysis, the average causal mediation effects is significant (ACME = 4.187, p = 0.012), meaning that there is an indirect effect of the IV (Depression) on the DV (Executive Networks) that goes through the mediator (Anxiety). However there is NO significant average direct effects (ADE = -2.622, p = 0.100) of the IV (Depression) on the DV (Executive Networks) as well as NO significant total effect of IV (Depression) on DV (Executive Networks) (p = 0.125)

Therefore, Anxiety can be considered as a causal result of Depression and a causal precursor of Network Executive performance.

     

      -END-