In 2016, a publication on health-related quality of life (HRQoL) assessment in patients with breast cancer reported on a systematic and standardized comparison of available instruments using the evaluation measures of patient-reported-outcomes (EMPRO) tool [
1]. In this review, eight HRQoL measures were compared including 32 studies reporting on psychometric properties or the validation process. One of the instruments included in this review is the International Breast Cancer Study Group (IBCSG) quality of life (QoL) Core Form [
2]. Although we are pleased that the IBCSG QoL Core Form could be recommended for assessing health-related quality of life in breast cancer [
1], the description of specific characteristics of the IBCSG form and the rating of this instrument based on EMPRO [
3] requires clarification and further discussion of the development research overlooked during the rating. Although Maratia et al. [
1] conducted a predefined systematic search and selection of papers, they used only a summary paper that was published in 1997 to describe the IBCSG approach [
2]. More detailed psychometric data for the IBCSG QoL Core Form have been published in many other studies as described in the following paragraphs. …