Value in Health Volume 22, Supplement 3S638
OBJECTIVES: The Study Medication Satisfaction Questionnaire status version (SMSQs) is a new measure designed for studies evaluating medication for HIV prevention (pre-exposure prophylaxis: PrEP) where participants do not have HIV. Adapted from the HIV Treatment Satisfaction Questionnaire (HIVTSQ) the SMSQs includes all aspects of treatment included in the HIVTSQ (e.g. convenience, side-effects). However, refers only to current ‘study medication’. This abstract reports the psychometric properties of the SMSQs.
METHODS: Data were from week 18 of the ÉCLAIR trial (NCT02076178): a randomised placebo-controlled clinical trial evaluating safety, tolerability and acceptability of cabotegravir long acting (LA) injectable formulation. Participants included healthy men, at low risk of contracting HIV, randomly assigned (5:1) to receive cabotegravir or placebo. By week 18, participants had received a once-daily oral cabotegravir (30mg) or placebo tablet for 4 weeks, and two intra-muscular injections of cabotegravir LA (800mg) or saline placebo (each at weeks 5 & 17). Data were available for 112 participants. The SMSQ includes 11 items exploring different aspects of medication satisfaction, rated on 7-point scales (e.g. 6 ‘very satisfied’ to 0 ‘very dissatisfied’).
RESULTS: Exploratory Factor Analysis (EFA) of the 11-item SMSQ revealed a clean one-factor structure explaining 65% of the variance. All items loaded >0.65. Internal consistency reliability was excellent (alpha=0.95). Repeated EFA explored use of an easy/difficult item as a potential alternative to the demands, flexibility and convenience items. No one combination demonstrated a superior solution (in each run loadings >0.63, explained variance >60 percent, alpha>0.91).
CONCLUSIONS: The SMSQ is an up-to-date appropriate measure of medication satisfaction for individuals at risk of HIV infection taking PrEP medication. Two versions of the SMSQs are available. For a more detailed analysis of medication satisfaction the full 11-item version is recommended. When brevity is paramount, an 8-item short-form (excluding demands, convenience and flexibility) can be used.