Assessing the reliability and validity of a newly developed insomnia treatment satisfaction questionnaire (ITSAT-Q)

To produce a valid insomnia treatment satisfaction questionnaire (ITSAT-Q) to assess treatment satisfaction with pharmacotherapy for use in patients with insomnia.

Items developed for a self-administered questionnaire were analyzed using exploratory factor analysis (EFA), which produced 5 dimensions. Confirmatory factor analysis was used to verify results from EFA, and structural equation modeling was used to test the hypothesized relationship among the dimensions. Data were collected from patients as part of a Sleep Research Project from January 2008 until October of 2008.

Approximately 69.8% of the sample (n=298) was female. Item-to-total correlations were 0.66 for convenience, ranged from 0.52 to 0.62 for expectations, from 0.54 to 0.69 for value, from 0.50 to 0.57 for effectiveness, and from 0.58 to 0.72 for treatment satisfaction. All standardized parameter estimates from confirmatory factor analysis were significant (p<0.01). Goodness of fit measures for the final structural equation model were chi(2)=45.2 (d.f.=45); p=0.465; CFI=1.00; TLI=1.00; and RMSEA=0.004. Treatment satisfaction was a strong and significant predictor of value, and effectiveness was a strong predictor of treatment satisfaction (p<0.01). Expectations were a strong and equal predictor of both treatment satisfaction and value (p<0.001).

The ITSAT-Q provided acceptable results for instrument reliability and validity. Findings from this study will provide additional insight regarding patient perceptions of treatment satisfaction and other related therapeutic dimensions to help prescribers assess pharmacotherapy.