Psychometric assessment of women with endometriosis

October 16, 2019

A newly published study in Expert Review of Pharmacoeconomics examined the impact of endometriosis on employment and household productivity.

Because endometriosis impacts health-related quality of life, a study has assessed the validity and responsiveness of the Health-Related Productivity Questionnaire, version 2 (HRPQ) specifically for employment and household productivity. The post hoc analysis in the journal Expert Review of Pharmacoeconomics used data from the Elaris Endometriosis I and II clinical trials (EM-1 and EM-2), consisting of 871 women (mean age 31.5) and 815 women (mean age 33.2), respectively. 

Methods
Participants in both trials were randomized in a 3:2:2 ratio to receive daily doses of either placebo, elagolix 150 mg once daily or elagolix 200 mg twice daily for 6 months. 

Due to the potential affect that endometriosis has on a person’s health-related quality of life (HRQL), “measuring absenteeism and presenteeism for both paid employment and household chores simultaneously is imperative and should be included as an evaluation endpoint during clinical product development,” the authors wrote.

Results
The self-reported, 9-item, 1-week recall HRPQ (version 2) used in the EM-I and EM-II trials revealed that the total hours of lost work among employed women were 16.5 and 15.2 per week, respectively, whereas the total hours of lost work among the household group were 8.3 and 8.4 per week, respectively. For employed women, absenteeism because of mild pain was 2.0 lost hours per week, from moderate pain 3.4 hours, and from severe pain 4.7 hours. Similarly, lost ability to work while on the job among employed women was 11.9, 13.5 and 16.4 lost hours per week, respectively.

Conclusions
“The HRPQ fills a gap in the current patient-reported landscape for work productivity instruments,” wrote the authors, noting that the tool can collect self-reported information about how both employment and household productivity is impacted, and is particularly useful for women of prime childrearing age.

“Often, productivity measurement is limited to employment and does not represent important domestic responsibilities,” the authors continued, pointing out that slightly over 20% of the women in both EM-1 and EM-2 were without paid employment. By failing to account for household responsibilities and their impact on productivity, the full burden of endometriosis on women is lacking. Therefore, treatment evaluations should include how patients feel, function, and survive, even if these variables are not work-related. 

In addition, the HRPQ can be used in interventional studies to assess how endometriosis impacts productivity. The Global Study of Women’s Health has also documented lost productivity due to endometriosis and its effect on HRQL. 

However, because the current study was a post hoc analysis, psychometric analyses to evaluate the reliability of the HRPQ, like reproducibility, were not performed, given that the design was not optimal for assessing reproducibility. Moreover, all data were based on self-report, thus increasing bias and limiting the potential accuracy of responses. Nonetheless, “The HRPQ is a valid and responsive tool for evaluating patient-reported productivity at work and at home among women with endometriosis,” the authors concluded.