18 CF Centers. 607 adolescents with CF, ages 11-20years.
Interventions
Centers were randomized to IMPACT (n=9; 300 adolescents), a brief problem-solving + education intervention, or standard care (SC; n=9; 307 adolescents). IMPACT was delivered during a regularly scheduled clinic visit by a member of the clinical care team.
Outcome measures
The primary outcome was composite pulmonary medication possession ratio (cMPR); secondary endpoints were lung function, Body Mass Index percentile, courses of IV antibiotics, and health-related quality of life at 12months.
Main results
Effectiveness of the intervention was tested using mixed models, generalized estimating equations comparing IMPACT to SC. 58%of problem-solving sessions targeted barriers to airway clearance, exercise or nutrition, while 18% addressed pulmonary medications. Average intervention fidelity score was 67% (SD=14%; Range=25-100%). No significant intervention effects were found for cMPR or any of the secondary outcomes compared to SC.
Authors' conclusions
The IMPACT intervention did not improve medication adherence or health outcomes over 12months. Challenges to implementing the intervention as intended during busy clinic visits were identified.