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Table 3 Analysis of primary and secondary outcomes in terms of contingency management

From: Clinical and cost-effectiveness of contingency management for cannabis use in early psychosis: the CIRCLE randomised clinical trial

Outcome Estimate* 95% CI N Estimate† 95% CI N
Time to acute psychiatric admission (HR) 1.03 (0.76, 1.40) 531 1.02 (0.75, 1.40) 531
Cannabis-positive urine sample 3 months (OR) 0.86 (0.56, 1.34) 354 0.85 (0.55, 1.32) 352
Cannabis-positive urine sample 18 months (OR) 0.84 (0.49, 1.41) 260 0.85 (0.50, 1.43) 260
log PANSS positive symptoms 3 months − 0.07 (− 0.14, − 0.00) 366 − 0.07 (− 0.14, − 0.00) 364
log PANSS positive symptoms 18 months −0.04 (− 0.13, 0.05) 276 − 0.04 (− 0.13, 0.04) 276
log PANSS negative symptoms 3 months − 0.08 (− 0.16, 0.00) 362 − 0.08 (− 0.16, 0.00) 360
log PANSS negative symptoms 18 months 0.01 (− 0.08, 0.11) 276 0.02 (− 0.08, 0.11) 276
Paid work or study at 3 months (OR) 0.95 (0.62, 1.46) 372 0.94 (0.60, 1.47) 370
Paid work or study at 18 months (OR) 0.82 (0.50, 1.35) 280 0.82 (0.50, 1.35) 280
Number of days cannabis used in the previous 12 weeks (3 months follow-up) (IRR) 0.89 (0.75, 1.04) 371 0.88 (0.75, 1.04) 369
Number of days cannabis used in the previous 6 months (18 months follow-up) (IRR) 1.09 (0.88, 1.36) 274 1.08 (0.87, 1.33) 274
Number of admissions over 18 months follow-up 1.08 (0.75, 1.54) 374 1.09 (0.76, 1.55) 374
At least one admission over 18 months follow-up (OR) 1.02 (0.70, 1.48) 531 1.01 (0.69, 1.48) 531
  1. CI confidence interval, HR hazard ratio, OR odds ratio, IRR incident rate ratio
  2. * Adjusting for level of cannabis use at baseline and whether in the pilot study
  3. † Additionally adjusting for baseline predictors of missingness. These are:
  4. Time to admission, number of admissions, at least one admission: any work or study
  5. Urine positive 3 months, PANSS positive 3 months, PANSS negative 3 months, any work or study 3 months, number of days cannabis use 3 months: exempt from work due to disability
  6. Urine positive 18 months: any work or study
  7. PANSS positive 18 months, PANSS negative 18 months, any work or study 18 months, number of days cannabis use 18 months: voluntary work