| Characteristic | Overall, N = 5731 | Treatment, N = 2921 | Control, N = 2811 | p-value2 |
|---|---|---|---|---|
| Performed by | ||||
| Radiology | 573 (100%) | 292 (100%) | 281 (100%) | |
| Department | 0.5 | |||
| Outpatient | 556 (97%) | 285 (98%) | 271 (96%) | |
| Inpatient | 14 (2.4%) | 5 (1.7%) | 9 (3.2%) | |
| Other | 3 (0.5%) | 2 (0.7%) | 1 (0.4%) | |
| Age (years) | 56 (41, 67) | 51 (36, 64) | 60 (49, 69) | <0.001 |
| Sex | <0.001 | |||
| Male | 233 (41%) | 86 (29%) | 147 (52%) | |
| Female | 340 (59%) | 206 (71%) | 134 (48%) | |
| Ketorolac | 268 (47%) | 268 (92%) | 0 (0%) | <0.001 |
| dose_amt_tor | <0.001 | |||
| 0 | 305 (53%) | 24 (8.2%) | 281 (100%) | |
| 15 | 114 (20%) | 114 (39%) | 0 (0%) | |
| 30 | 148 (26%) | 148 (51%) | 0 (0%) | |
| 45 | 3 (0.5%) | 3 (1.0%) | 0 (0%) | |
| 60 | 3 (0.5%) | 3 (1.0%) | 0 (0%) | |
| dose_nbr_tor | <0.001 | |||
| 0 | 305 (53%) | 24 (8.2%) | 281 (100%) | |
| 1 | 249 (43%) | 249 (85%) | 0 (0%) | |
| 2 | 19 (3.3%) | 19 (6.5%) | 0 (0%) | |
| dosage_tor | >0.9 | |||
| (0, 15] | 128 (48%) | 128 (48%) | 0 (NA%) | |
| (15, 30] | 137 (51%) | 137 (51%) | 0 (NA%) | |
| > 30 | 3 (1.1%) | 3 (1.1%) | 0 (NA%) | |
| Unknown | 305 | 24 | 281 | |
| Hydromorphone | 44 (7.7%) | 44 (15%) | 0 (0%) | <0.001 |
| dose_amt_dil | <0.001 | |||
| 0 | 529 (92%) | 248 (85%) | 281 (100%) | |
| (0.2, 0.5] | 32 (5.6%) | 32 (11%) | 0 (0%) | |
| (0.5, 1.0] | 8 (1.4%) | 8 (2.7%) | 0 (0%) | |
| > 1.0 | 4 (0.7%) | 4 (1.4%) | 0 (0%) | |
| dose_nbr_dil | <0.001 | |||
| 0 | 529 (92%) | 248 (85%) | 281 (100%) | |
| 1 | 36 (6.3%) | 36 (12%) | 0 (0%) | |
| 2 | 6 (1.0%) | 6 (2.1%) | 0 (0%) | |
| 3 | 1 (0.2%) | 1 (0.3%) | 0 (0%) | |
| 4 | 1 (0.2%) | 1 (0.3%) | 0 (0%) | |
| dosage_dil | 0.30 (0.20, 0.50) | 0.30 (0.20, 0.50) | NA (NA, NA) | |
| Unknown | 530 | 249 | 281 | |
| Received both | 22 (3.8%) | 22 (7.5%) | 0 (0%) | <0.001 |
| Other_Med_Given | 0.042 | |||
| 1.0 | 8 (29%) | 5 (20%) | 3 (100%) | |
| 2.0 | 18 (64%) | 18 (72%) | 0 (0%) | |
| 3.0 | 2 (7.1%) | 2 (8.0%) | 0 (0%) | |
| Unknown | 545 | 267 | 278 | |
| pre_AST | 40 (25, 70) | 38 (24, 66) | 43 (27, 75) | 0.078 |
| Unknown | 172 | 84 | 88 | |
| pre_AST2 | 0.13 | |||
| < 34 | 163 (41%) | 92 (44%) | 71 (37%) | |
| ≥ 34 | 238 (59%) | 116 (56%) | 122 (63%) | |
| Unknown | 172 | 84 | 88 | |
| pre_ALT | 42 (24, 95) | 38 (22, 90) | 48 (25, 100) | 0.069 |
| Unknown | 168 | 81 | 87 | |
| pre_ALT2 | 0.067 | |||
| < 55 | 234 (58%) | 131 (62%) | 103 (53%) | |
| ≥ 55 | 171 (42%) | 80 (38%) | 91 (47%) | |
| Unknown | 168 | 81 | 87 | |
| pre_ALKP | 110 (81, 185) | 105 (78, 156) | 119 (85, 232) | 0.012 |
| Unknown | 178 | 86 | 92 | |
| pre_ALKP2 | 0.004 | |||
| < 150 | 258 (65%) | 148 (72%) | 110 (58%) | |
| ≥ 150 | 137 (35%) | 58 (28%) | 79 (42%) | |
| Unknown | 178 | 86 | 92 | |
| pre_INR | 1.00 (1.00, 1.10) | 1.00 (1.00, 1.10) | 1.00 (1.00, 1.10) | 0.2 |
| Unknown | 60 | 37 | 23 | |
| pre_INR2 | 0.15 | |||
| < 1.2 | 424 (83%) | 217 (85%) | 207 (80%) | |
| ≥ 1.2 | 89 (17%) | 38 (15%) | 51 (20%) | |
| Unknown | 60 | 37 | 23 | |
| Anticoag_Type | <0.001 | |||
| None | 413 (72%) | 236 (81%) | 177 (63%) | |
| Blood thinner | 35 (6.1%) | 18 (6.2%) | 17 (6.0%) | |
| AntiPLT | 116 (20%) | 36 (12%) | 80 (28%) | |
| Blood thinner + AntiPLT | 9 (1.6%) | 2 (0.7%) | 7 (2.5%) | |
| pre_PLT | 240 (179, 293) | 244 (194, 299) | 227 (166, 287) | 0.061 |
| Unknown | 85 | 42 | 43 | |
| Hgb_drawn_postbx | 33 (5.8%) | 9 (3.1%) | 24 (8.5%) | 0.005 |
| Hgb_drop | 7 (19%) | 2 (18%) | 5 (20%) | >0.9 |
| Unknown | 537 | 281 | 256 | |
| Hypotension | 5 (0.9%) | 2 (0.7%) | 3 (1.1%) | 0.7 |
| Unknown | 25 | 6 | 19 | |
| Level_of_Care | 0.3 | |||
| 1 | 9 (1.6%) | 7 (2.4%) | 2 (0.7%) | |
| 2 | 14 (2.4%) | 8 (2.7%) | 6 (2.1%) | |
| 3 | 11 (1.9%) | 4 (1.4%) | 7 (2.5%) | |
| 4 | 530 (92%) | 270 (92%) | 260 (93%) | |
| 5 | 9 (1.6%) | 3 (1.0%) | 6 (2.1%) | |
| Indication_code | <0.001 | |||
| Liver function abnormality | 210 (37%) | 122 (42%) | 88 (31%) | |
| Liver lesion evaluation | 335 (58%) | 168 (58%) | 167 (59%) | |
| Liver transplant elevated LFTs | 28 (4.9%) | 2 (0.7%) | 26 (9.3%) | |
| Death_within_30d | 8 (1.4%) | 3 (1.0%) | 5 (1.8%) | 0.5 |
| Biopsy_target | <0.001 | |||
| Target | 327 (57%) | 163 (56%) | 164 (58%) | |
| Random | 219 (38%) | 127 (43%) | 92 (33%) | |
| Txp | 27 (4.7%) | 2 (0.7%) | 25 (8.9%) | |
| 1 n (%); Median (IQR) | ||||
| 2 Fisher’s exact test; Wilcoxon rank sum test; Pearson’s Chi-squared test | ||||
Predictors of pain medication after liver biopsy
Statistical analysis
Categorical variables are summarized as counts and percentages, continuous variables as median and interquartile range (IQR). The treatment group is compared to the control group using Fisher’s exact test for categorical variables and Wilcoxon rank-sum test for continuous variables. A multiple logistic regression model is fitted to assess the association of predictors with treatment vs control. P values are two-sided and considered significant at the 0.05 level. The analysis is performed using R version 4.3.2 (R Core Team, 2025).
Decriptive anaysis
The initial dataset contains 669 subjects, of which 96 (14.3%) are excluded. The remaining 573 subjects meet inclusion criteria Exclude == 1. Subjects demographics, lab values, pathology and imaging data are tabulated by treatment vs control in Table 1, Table 2, and Table 3.
Demographics and labs
Pathology
Some levels may need to be combined.
| Characteristic | Overall, N = 5731 | Treatment, N = 2921 | Control, N = 2811 | p-value2 |
|---|---|---|---|---|
| Pathology_Mets | 0.056 | |||
| Mets | 226 (40%) | 104 (36%) | 122 (44%) | |
| No Mets | 345 (60%) | 187 (64%) | 158 (56%) | |
| Unknown | 2 | 1 | 1 | |
| Pathology_TM | 0.063 | |||
| No non-cirrhotic liver injury | 445 (78%) | 236 (81%) | 209 (75%) | |
| Non-cirrhotic liver injury | 126 (22%) | 55 (19%) | 71 (25%) | |
| Unknown | 2 | 1 | 1 | |
| Pathology_SHF | 0.5 | |||
| 0 | 373 (65%) | 186 (64%) | 187 (67%) | |
| 1 | 57 (10.0%) | 31 (11%) | 26 (9.3%) | |
| 2/3 | 44 (7.7%) | 26 (8.9%) | 18 (6.4%) | |
| 4 | 33 (5.8%) | 20 (6.9%) | 13 (4.6%) | |
| 5 | 39 (6.8%) | 18 (6.2%) | 21 (7.5%) | |
| 6 | 25 (4.4%) | 10 (3.4%) | 15 (5.4%) | |
| Unknown | 2 | 1 | 1 | |
| Pathology_Biliary | 0.4 | |||
| 0 | 503 (88%) | 258 (89%) | 245 (88%) | |
| 1,5 | 25 (4.4%) | 9 (3.1%) | 16 (5.7%) | |
| 2-4 | 16 (2.8%) | 10 (3.4%) | 6 (2.1%) | |
| 6-7 | 26 (4.6%) | 14 (4.8%) | 12 (4.3%) | |
| 8 | 1 (0.2%) | 0 (0%) | 1 (0.4%) | |
| Unknown | 2 | 1 | 1 | |
| Pathology_BenignOther | 0.033 | |||
| 0 | 490 (86%) | 237 (81%) | 253 (90%) | |
| 1-2,7-8 | 35 (6.1%) | 24 (8.2%) | 11 (3.9%) | |
| 3 | 11 (1.9%) | 8 (2.7%) | 3 (1.1%) | |
| 4 | 29 (5.1%) | 19 (6.5%) | 10 (3.6%) | |
| 5-6 | 6 (1.1%) | 3 (1.0%) | 3 (1.1%) | |
| Unknown | 2 | 1 | 1 | |
| Pathology_Txp | 0.001 | |||
| 0 | 557 (98%) | 290 (100%) | 267 (95%) | |
| 1 | 5 (0.9%) | 0 (0%) | 5 (1.8%) | |
| 2 | 4 (0.7%) | 0 (0%) | 4 (1.4%) | |
| 3 | 5 (0.9%) | 1 (0.3%) | 4 (1.4%) | |
| Unknown | 2 | 1 | 1 | |
| 1 n (%) | ||||
| 2 Pearson’s Chi-squared test; Fisher’s exact test | ||||
Imaging and others
| Characteristic | Overall, N = 5731 | Treatment, N = 2921 | Control, N = 2811 | p-value2 |
|---|---|---|---|---|
| US_post | 0.7 | |||
| 1 | 534 (93%) | 270 (92%) | 264 (94%) | |
| 2 | 10 (1.7%) | 7 (2.4%) | 3 (1.1%) | |
| 3 | 24 (4.2%) | 12 (4.1%) | 12 (4.3%) | |
| 4 | 4 (0.7%) | 2 (0.7%) | 2 (0.7%) | |
| 5 | 1 (0.2%) | 1 (0.3%) | 0 (0%) | |
| Post_US_image | 0.5 | |||
| 1 | 39 (6.8%) | 22 (7.5%) | 17 (6.0%) | |
| 2 | 534 (93%) | 270 (92%) | 264 (94%) | |
| CT_postBx | 0.029 | |||
| 1 | 553 (97%) | 277 (95%) | 276 (98%) | |
| 2 | 20 (3.5%) | 15 (5.1%) | 5 (1.8%) | |
| CT_Finding | 4 (22%) | 3 (21%) | 1 (25%) | >0.9 |
| Unknown | 555 | 278 | 277 | |
| CT_Finding_type | 0.7 | |||
| 1 | 10 (77%) | 7 (78%) | 3 (75%) | |
| 2 | 1 (7.7%) | 1 (11%) | 0 (0%) | |
| 3 | 1 (7.7%) | 0 (0%) | 1 (25%) | |
| 4 | 1 (7.7%) | 1 (11%) | 0 (0%) | |
| Unknown | 560 | 283 | 277 | |
| SecondLook_US_Finding | 3 (7.7%) | 3 (9.4%) | 0 (0%) | >0.9 |
| Unknown | 534 | 260 | 274 | |
| PainScore_10p | <0.001 | |||
| Median (IQR) | 0 (0, 6) | 6 (3, 8) | 0 (0, 0) | |
| Mean (SD) | 846 (2,782) | 1,000 (2,999) | 712 (2,575) | |
| Unknown | 99 | 71 | 28 | |
| PainScore_Y_N | 284 (53%) | 236 (86%) | 48 (18%) | <0.001 |
| Unknown | 37 | 16 | 21 | |
| BiopsyDevice_code | 0.2 | |||
| 1 | 488 (97%) | 225 (95%) | 263 (98%) | |
| 2 | 6 (1.2%) | 3 (1.3%) | 3 (1.1%) | |
| 3 | 8 (1.6%) | 6 (2.5%) | 2 (0.7%) | |
| 4 | 2 (0.4%) | 2 (0.8%) | 0 (0%) | |
| Unknown | 69 | 56 | 13 | |
| PassLength_CM | 2.30 (2.30, 3.30) | 2.40 (2.20, 3.30) | 2.30 (2.30, 3.30) | 0.4 |
| Unknown | 24 | 14 | 10 | |
| Biopsy_gauge | ||||
| 18 | 560 (100%) | 285 (100%) | 275 (100%) | |
| Unknown | 13 | 7 | 6 | |
| Biopsy_side | <0.001 | |||
| 1.0 | 304 (53%) | 179 (61%) | 125 (44%) | |
| 2.0 | 194 (34%) | 83 (28%) | 111 (40%) | |
| 3.0 | 2 (0.3%) | 0 (0%) | 2 (0.7%) | |
| 4.0 | 3 (0.5%) | 1 (0.3%) | 2 (0.7%) | |
| 9999.0 | 64 (11%) | 28 (9.6%) | 36 (13%) | |
| Both | 6 (1.0%) | 1 (0.3%) | 5 (1.8%) | |
| Num_pass | 0.13 | |||
| Mean (SD) | 2.00 (1.13) | 2.04 (1.10) | 1.95 (1.16) | |
| Unknown | 2 | 1 | 1 | |
| Time_to_med | 0.024 (0.014, 0.036) | 0.024 (0.014, 0.036) | 0.015 (0.015, 0.015) | 0.5 |
| Unknown | 285 | 5 | 280 | |
| 1 n (%); Median (IQR) | ||||
| 2 Fisher’s exact test; Pearson’s Chi-squared test; Wilcoxon rank sum test | ||||
Multivariate analysis
A multiple logistic regression model for the probability of control (vs treatment) is fitted against age, sex, pre-ALKP, anticoagulation type, post-biopsy Hgb drawn, indication code, biopsy target, pathology benign other, pathology transplant, and biopsy side. The results are summarized in Table 4.
| Characteristic | OR1 | 95% CI1 | p-value |
|---|---|---|---|
| Age (years) | 1.04 | 1.02, 1.06 | <0.001 |
| Sex | <0.001 | ||
| Male | — | — | |
| Female | 0.32 | 0.19, 0.52 | |
| pre_ALKP2 | 0.2 | ||
| < 150 | — | — | |
| ≥ 150 | 1.41 | 0.85, 2.32 | |
| Anticoag_Type | 0.4 | ||
| None | — | — | |
| Blood thinner | 0.87 | 0.33, 2.25 | |
| AntiPLT | 1.79 | 0.88, 3.73 | |
| Blood thinner + AntiPLT | 0.99 | 0.10, 10.3 | |
| Hgb_drawn_postbx | 0.066 | ||
| No | — | — | |
| Yes | 0.17 | 0.01, 1.11 | |
| Indication_code | 0.14 | ||
| Liver function abnormality | — | — | |
| Liver lesion evaluation | 1.48 | 0.31, 6.78 | |
| Liver transplant elevated LFTs | 147,835,242 | 0.00, NA | |
| Biopsy_target | 0.8 | ||
| Target | — | — | |
| Random | 1.39 | 0.29, 6.45 | |
| Txp | 0.00 | ||
| Pathology_BenignOther | 0.040 | ||
| 0 | — | — | |
| 1-2, 7-8 | 0.29 | 0.06, 1.12 | |
| 3 | 0.30 | 0.04, 1.52 | |
| 4 | 0.28 | 0.07, 0.89 | |
| 5-6 | 2.29 | 0.24, 52.4 | |
| Pathology_Txp | 0.70 | 0.25, 2.36 | 0.5 |
| Biopsy_side | 0.005 | ||
| Right | — | — | |
| Left | 1.88 | 1.12, 3.16 | |
| Central/Bilateral | 38,424,716 | 0.00, NA | |
| Missing | 1.18 | 0.54, 2.56 | |
| 1 OR = Odds Ratio, CI = Confidence Interval | |||