Strengths and Limitations
SECONDARY, BLIND
Strengths of our study include the use of between-group structural equivalence and blind assessment. Furthermore, outcomes of interest (methadone doses and number of treatment days) were based on objective measures, extracted from patient records.This trial has limitations. It was not powered to detect group differences for outcomes other than methadone dose; secondary outcome differences could be artifactual. Additionally, open-label interventions are inherently incompatible with double-blinding. Previous open-label RCTs have been only assessor blinded; ours is one of the few in which the blind extended to the clinicians. Personal communications between the lead author (A.M.B.) and these individuals (treatment physicians [A.D.G., E.W.] and the nurse practitioner) suggest that this blind was not broken (ie, clinicians were not even aware of their patients’ study involvement). Despite this, the possibility still exists that C-OLP participants discussed the study with treatment team members. Furthermore, this study was conducted in a single setting—findings from which may not be generalizable to other treatment settings and populations. A planned larger trial will address this shortcoming. A final limitation is that we did not quite achieve our intended sample size of 60 participants in the TAU group.