Table 2.

Outcomes and covariates and their measurement details.

Outcomes and covariates		Measure	Collection point	Response type or analysis	Statistical test
Primary patient-reported outcomes
	Risk awareness and recall	Opioid Risk Tool and risk assessment recall	Baseline, day 14, and at 3 months	Ordinal (three options) for baseline risk and risk recall	Cohen weighted kappa (within treatment arm) and χ2 tests (crude agreement)
	Self-reported opioid use	Yes or no if taking opioids	Days 1, 2, 4-6, and 14 and at 3 months	Dichotomous (yes or no)	Zero-inflated negative binomial or zero-inflated Poisson models
	Patient-reported preference for pain relief	Patient pain relief preference survey	Baseline	Five options for patient-reported pain relief preference	Cochran-Armitage χ2 test for trend
	Agreement on pain treatment between patient preference and provider decision	Patient preference vs electronic medical record documentation		Five options for patient-reported pain preference and concordance with provider decision	Cohen weighted kappa, intraclass correlation coefficient, Bland-Altman plots (within treatment arm), and χ2 tests (crude agreement)
Secondary patient-reported outcomes
	Days to no opioid use	Number of pain medications taken daily	Days 1,2, 4-6, and 14 and at 3 months	Continuous (number of pills of each type)	Kaplan Meier and proportional hazards (time to full functionality)
	Functional status	Back Pain Functional Scale and the 20-Item Short Form Survey from the Medical Outcomes Study	Days 1, 7, and 14 and at 3 months	Likert scale (0-10) and composite score for five items (0-50)	Kaplan Meier, proportional hazards (time to full functionality), and random-effects mixed model  to measure clinically important changes in functionality
	Satisfaction with pain treatment	American Pain Society Patient Outcome Questionnaire	Baseline; days 1, 7, and 14; and at 3 months	Likert scale (1-6) and dichotomous (satisfied vs not satisfied)	χ2 tests, Mantel-Haenszel summary statistics, and general linear model with log-linear link
	Trust in provider	Trust in Physician Scale	Day 7	Likert scale (1-5) and composite score for 11 items (11-55)	Analysis of variance or Kruskal-Wallis test
	Follow-up visits for pain	Self-report of additional provider visits	Day 14 and at 3 months	Dichotomous (yes or no visits; yes or no provide pain pills)	χ2 test and general linear model with log-linear link
	Patient-reported measure of shared decision making	CollaboRATE	Day 1	Likert scale (1-10)	Analysis of variance or Kruskal-Wallis test
	Opioid misuse	Current Opioid Misuse Measure	At 3 months	Dichotomous score (≥9 vs <9)	χ2 test and general linear model with log-linear link
Covariates (subgroup analyses)
	Demographics	GENACISa and BRFSSb 2011	Baseline	Varies by question	N/Ac
	Overall health	Self-rated health	Baseline and at 3 months	Likert scale (1-5)	N/A
	Medical condition (back vs renal colic)	ICD-9d codes and primary complaint	Baseline	ICD-9 codes	N/A
	Medical history	Electronic health record	Baseline	ICD-9 codes	N/A
	Risk for opioid dependency	Opioid Risk Tool	Baseline	Continuous score (0-26) risk level (high, medium, or low)	N/A

^aGENACIS: Gender, Alcohol, and Culture: An International Study.

^bBRFSS: Behavioral Risk Factor Surveillance System.

^cN/A: not applicable. As these were not outcomes, we do not report statistical tests; these are listed as covariates.

^dICD-9: International Classification of Diseases, Ninth Revision.