OBJECTIVES:  The aim of this literature review was to assess the frequency of Rasch analysis use in Patient-Reported Outcomes (PRO) validation according to the year, the therapeutic area (TA) and the concept to be measured. METHODS:  A literature search was conducted in Medline and Embase from 1970 up to June 2016 to identify articles reporting the validation of PRO using Rasch. RESULTS:  A total of 3,284 references using Rasch analysis were retrieved. An exponential increase was observed, from 1 article in 1977 up to 400 articles in 2015. In June 2016, already 200 articles have been published. Significant shifts were observed over the four decades, including one in 2007 and another in 2009. These two shifts followed the release of the U.S. FDA PRO guidance highlighting the importance of content validity (e.g. scoring of items and domains, response options, assessment of concept spectrum coverage). Indeed, item and person fit indices plus benefits of a person-item map provided by Rasch can be real added values when assessing content validity. Preliminary analyses showed that the number of references varied widely across TAs: Rasch was used mostly in psychology-psychiatry (32%) and central nervous system (CNS) (23%), then ophthalmology (11%), musculoskeletal disorders-rheumatology (10%), and oncology (5%). Guidance that could explain this special interest for Rasch in these particular TAs will be further explored. In addition, the use of Rasch according to the nature of the concept measured (symptom, function, health-related quality of life), and the context (validation of specific property, i.e. unidimensionality; use of item bank; need of standardized measurement) will be documented. CONCLUSIONS:  The use of Rasch analysis for PRO questionnaire validation is in constant progression. It is particularly used in the fields of psychology-psychiatry and CNS. The next step will consist of identifying the drivers of the rapid recent increase and shifts.