The Quality of Marriage Index (QMI): a validation study in infertile patients

OBJECTIVE: Infertility can have a considerable effect on a person’s marital satisfaction. The Quality of Marriage Index (QMI) is a self-report inventory to measure global perceptions of marital satisfaction. The current study examined the reliability and validity of the Persian language version of QMI in a sample of infertile patients. RESULTS: The mean QMI total score was 36.54 ± 6.87. The internal consistency of the scale was good, with a Cronbach’s alpha of 0.922. All inter-item correlations and item-total correlations were also in acceptable range. The confirmatory factor analysis results provided evidence for unidimensionality of the scale (χ(2)/df = 3.10; GFI = 0.97; CFI = 0.99; NFI = 0.99; RMSEA = 0.091 and SRMR = 0.020). The convergent validity of the QMI was demonstrated via significant correlations with measures of the Relationship Assessment Scale, Kansas Marital Satisfaction Scale, and Couples Satisfaction Index-4 Item. These correlations also tended to be larger than correlations with measures of Hospital Anxiety and Depression Scale and Perceived Stress Scale-4 Item. Among demographic/fertility variables, only infertility duration was negatively correlated to QMI scores. In sum, the QMI is a reliable and valid brief inventory for measuring overall marital satisfaction in infertile patients. Trial registration This was a cross-sectional study (NOT clinical trial); thus, the trail registration number is not required for the present study