Beliefs About Medicines in Patients with Hypertension: the Instrument Validity and Reliability in Iran

Abstract

Purpose:Despite the importance of patients believes as one of the most important predictors of treatment adherence behavior, it is rarely considered in numerous studies. Then the current survey was aimed to develop and study the beliefs about medicines questionnaire (BMQ) in patients with hypertension.Materials and Methods:The BMQ developed by Horn and et al. was used in the current study. This questionnaire included 18 questions in both public and private beliefs regarding drug. Face and content validity of the tool was investigated using expert’s panel. In final, aforementioned tool was tested in 612 participants. To explore structure validity and internal consistency, exploratory and confirmatory factor analysis and alpha coefficient was conducted. To evaluate the final validity of instrument, the mean score of the beliefs about medicines of patients with appropriate medication adherence were compared to patients without medication adherence.Results:The mean age of patients was 44.08 ± 10.38 years. Women were 314 of participants. Calculated face validity by the impact score for each item indicated that all the items of the questionnaire had the impact score of more than 1.5. In total, all items had scored higher than 0.79 by considering 18 items for content validity. The average of content validity index for the questionnaire was 0.93. Load of factors were in the range of 0.51 to 0.79. Four items explained % 57 of the total variance. Comparison of all instrument items in the two groups showed that patients with good adherence had higher score in 15 items (% 83 of all items).Conclusion:The findings suggested that the BMQ in patients with hypertension as a valid and reliable instrument can be used to evaluate the patients’ medication adherence.

Reliability and validity of Beliefs on Medicine Questionnaire (BMQ) in diabetes mellitus patients: Malay Translated Version

“…The findings from the confirmatory factor analysis of Malay BMQ were similar to the ones reported by Mostafavi (2016) for Persian BMQ. Persian BMQ which was validated among hypertensive patients produced a fit model with CFI values of 0.958 and RMSEA of 0.073 16 . Similarly, in the present study, the Malay BMQ was reported with good construct validity, having a CFI value of greater than 0.9 and RMSEA as high as 0.067.…”

“…Both studies reported good and reliable internal consistencies. Similarly, Salgado (2013) and Mostafavi (2016) also reported good internal consistencies with Cronbachs' alpha value that was greater than 0.6 but with two constructs extracted for BMQ-General as in the original BMQ 16,17 .…”

“…The Spanish version of BMQ reported with identical factor loadings as the original four constructs and is considered as a reliable tool to measure beliefs in medicine among Type 2 Diabetes Mellitus (DM) patients 12 . Similarly, BMQ which has been adapted and validated on different sets of diseased populations and resulted in similar construct as in the original version 15,16,17,18 . However, ISSN 2250-3153 http://dx.doi.org/10.29322/IJSRP.9.02.2019.p8609 www.ijsrp.org to our knowledge there is no Malay version of BMQ to date.…”

“…) which has translated BMQ indicated similar patient criteria where the average patient's age is within the range of 44-56 years similar to the present study with an average of 51 years and an average of 50% of patients were male. The original BMQ was translated into Portuguese, Persian, French, Maltese and other versions11,15,16,17,32,33,34 . The translated BMQ has been validated among hypertensive, psychiatric, mental illnesses, asthmatic and diabetic patients 11,15,16 .…”

Cross-cultural Adaptation and Validation of Beliefs about Medicines Questionnaire on Asthma and Chronic Obstructive Pulmonary Disease Patients

“…In the French study, they have shown that four-factor model similar to the original study revealed CFI as 0.89 and RMSEA as 0.08 [23]. Also, a Persian study revealed CFI as 0.96, NFI as 0.96, and RMSEA as 0.07 [24]. All these results are consistent with those of ours and show the validity of the Turkish version of BMQ.…”