Validation of a general measure of treatment satisfaction, the Treatment Satisfaction Questionnaire for Medication (TSQM), using a national panel study of chronic disease.
BACKGROUND
The objective of this study was to develop and psychometrically evaluate a general measure of patients' satisfaction with medication, the Treatment Satisfaction Questionnaire for Medication (TSQM).


METHODS
The content and format of 55 initial questions were based on a formal conceptual framework, an extensive literature review, and the input from three patient focus groups. Patient interviews were used to select the most relevant questions for further evaluation (n = 31). The psychometric performance of items and resulting TSQM scales were examined using eight diverse patient groups (arthritis, asthma, major depression, type I diabetes, high cholesterol, hypertension, migraine, and psoriasis) recruited from a national longitudinal panel study of chronic illness (n = 567). Participants were then randomized to complete the test items using one of two alternate scaling methods (Visual Analogue vs. Likert-type).


RESULTS
A factor analysis (principal component extraction with varimax rotation) of specific items revealed three factors (Eigenvalues > 1.7) explaining 75.6% of the total variance; namely Side effects (4 items, 28.4%, Cronbach's Alpha =.87), Effectiveness (3 items, 24.1%, Cronbach's Alpha =.85), and Convenience (3 items, 23.1%, Cronbach's Alpha =.87). A second factor analysis of more generally worded items yielded a Global Satisfaction scale (3 items, Eigenvalue = 2.3, 79.1%, Cronbach's Alpha =.85). The final four scales possessed good psychometric properties, with the Likert-type scaling method performing better than the VAS approach. Significant differences were found on the TSQM by the route of medication administration (oral, injectable, topical, inhalable), level of illness severity, and length of time on medication. Regression analyses using the TSQM scales accounted for 40-60% of variation in patients' ratings of their likelihood to persist with their current medication.


CONCLUSIONS
The TSQM is a psychometrically sound and valid measure of the major dimensions of patients' satisfaction with medication. Preliminary evidence suggests that the TSQM may also be a good predictor of patients' medication adherence across different types of medication and patient populations.
Worldwide Outcomes Research, La Jolla Laboratories, Pfizer Inc, 10777 Science Center Drive (B-95), San Diego, CA 92121-1111, USA. mark.j.atkinson@pfizer.com
Mark J
MJ
Atkinson
Anusha
A
Sinha
Steven L
SL
Hass
Shoshana S
SS
Colman
Ritesh N
RN
Kumar
Meryl
M
Brod
Clayton R
CR
Rowland
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease / Q000145:classification / Q000188:drug therapy*; D004333:Drug Administration Routes; D064420:Drug-Related Side Effects and Adverse Reactions; D005163:Factor Analysis, Statistical; D019538:Health Care Surveys; D006801:Humans; D008875:Middle Aged; D010349:Patient Compliance / Q000523:psychology / Q000706:statistics & numerical data; D017060:Patient Satisfaction / Q000706:statistics & numerical data*; D004364:Pharmaceutical Preparations / Q000008:administration & dosage; D011594:Psychometrics / Q000295:instrumentation*; D036301:Qualitative Research; D012044:Regression Analysis; D012646:Self Administration / Q000523:psychology* / Q000706:statistics & numerical data; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D014481:United States
D004364:Pharmaceutical Preparations