Numerous studies concerning endometriosis and pain have been reported. However, there is no consensus on the best method to evaluate pain in endometriosis and many scales have been used. Moreover, there are only a few descriptions of minimal clinically important differences after treatment (MCID) to evaluate variations in pain. In our study, we aim to identify pain scales used in endometriosis pain treatment, to address their strong and weak points and to define which would be the ideal scale to help clinicians and researchers to evaluate endometriosis-related pain. A search of the MEDLINE and EMBASE databases was carried out for publications in English, French or Portuguese from 1980 to December 2012, for the words: endometriosis, treatment, pain. Studies were selected if they studied an endometriosis treatment and a pain scale was specified. A quantitative and a qualitative analysis of each scale was performed to define strong and weak points of each scale (systematic registration number: CRD42013005336). A total of 736 publications were identified. After excluding duplications and applying inclusion criteria 258 studies remained. We found that the visual analog scale (VAS) is the most frequently used scale. Both VAS and the numerical rating scale (NRS) show a good balance between strong and weak points in comparison with others such as the Biberoglu and Behrman scale. Concerning MCID, only VAS, NRS and Brief Pain Inventory scales have reported MCID and, among these, only VAS MCID has been studied in endometriosis patients (VAS MCID = 10 mm). Adding the Clinical Global Impression score (CGI) to the pain scale allows calculation of the MCID. When using pain scales their strengths and weaknesses must be known and included in the analysis. VAS is the most frequently used pain scale and, together with NRS, seems the best adapted for endometriosis pain measurement. The use of VAS or NRS for each type of typical pain related to endometriosis (dysmenorrhea, deep dyspareunia and non-menstrual chronic pelvic pain), combined with the CGI and a quality-of-life scale will provide both clinicians and researchers with tools to evaluate treatment response.

Endometriosis and quality of life has been the subject of much research, however, there is little consensus on how best to evaluate quality of life in endometriosis, resulting in many and diverse scales being used. In our study, we aim to identify quality of life scales used in endometriosis, to review their strengths and weaknesses and to establish what would define an ideal scale in the evaluation of endometriosis-related quality of life. A search of the MEDLINE and EMBASE databases was carried out for publications in English and French for the period from 1980 to February 2017, using the words ‘endometriosis’ and ‘quality of life’. Publications were selected if they reported on quality of life in patients with endometriosis and specified use of a quality of life scale. A quantitative and a qualitative analysis of each scale was performed in order to establish the strengths and weaknesses for each scale (systematic registration number: PROSPERO 2014: CRD42014014210). A total of 1538 articles publications were initially identified. After exclusion of duplicates and application of inclusion criteria, 201 studies were selected for analysis. The SF-36, a generic HRQoL measure, was found to be the most frequently used scale, followed by the EHP-30, a measure specific to endometriosis. Both perform well, when compared with other scales, with scale weaknesses offset by strengths. EHP-5 and EQ-5D also showed to be of good quality. All four were the only scales to report on MCID studied in endometriosis patients. For clinical practice, routine evaluation of HRQOL in women with endometriosis is essential both for health-care providers and patients. Both SF-36 and EHP-30 perform better overall with regard to their strengths and weaknesses when compared to other scales.