Comparing treatment fidelity between study arms of a randomized controlled clinical trial for stroke family caregivers

Abstract

Objective:

To compare treatment fidelity among treatment arms in the Telephone Assessment and Skill-Building Kit study for stroke caregivers (TASK II) with respect to: 1) protocol adherence; 2) intervention dosage and 3) nurse intervener perspectives.

Design:

A randomized controlled clinical trial design.

Setting:

Urban, community, midwestern United States.

Subjects:

A total of 254 stroke caregivers (mean ±SD age, 54.4 ±11.8 years), 55 (22.0%) males and 199 (78.4%) females) randomized to the TASK II intervention (n=123) or an Information, Support, and Referral comparison group (n=131).

Interventions:

TASK II participants received the TASK II Resource Guide; Information, Support, and Referral participants received a standard caregiver brochure. At approximately 8 weeks after discharge, both groups received 8 weekly calls from a nurse, with a booster call 4 weeks later.

Measures:

Protocol adherence was evaluated with the TASK II Checklist for Monitoring Adherence. Intervention dosage was measured by the number of minutes caregivers spent reading materials and talking with the nurse. Nurse intervener perspectives were obtained through focus groups.

Results:

Protocol adherence was 80% for the TASK II and 92% for the Information, Support, and Referral. As expected, intervention dosage differed between TASK II and Information, Support, and Referral with respect to caregiver time spent reading materials (t=-6.49; P<.001) and talking with the nurse (t=-7.38; P<.001). Focus groups with nurses yielded further evidence for treatment fidelity and recommendations for future trials.

Conclusions:

These findings substantiate treatment fidelity in both study arms of the TASK II stroke caregiver intervention trial (NIH R01NR010388; ClinicalTrials.govNCT01275495).