**2. Methods**

### **2.1 Search strategy**

A comprehensive literature search was performed in the following databases, PubMed, EMBASE, Scopus, CINAHL, Medline and Science Direct, for articles on posture and back shape from 1980 to 2017. The search keywords were 'posture', 'back shape', 'spinal mobility', 'postural assessment', 'back surface measurement', 'postural alignment', 'posture' and 'reproducibility', 'posture' and 'reliability', 'posture' and 'accuracy', 'posture' and 'validity', 'posture' and 'spinal pain' and 'posture' and 'low back pain'. The author also combined each human body segment with 'posture' as keywords, 'head posture', 'neck posture', 'cervical posture', 'thoracic posture', 'trunk posture', 'lumbar posture', 'shoulder posture', 'arm posture', 'upper limb posture' and 'lower limb posture'. In addition, the author searched for related articles from references cited in the articles identified from the original search. The search was limited to articles only written in English. No wildcards were used in this study.

### **2.2 Criteria for inclusion and exclusion**

All articles that assessed posture and back shape were considered in order to identify all possible methods for the evaluation of posture. Reviews of postural assessment and articles that discussed posture in some manner that could help the discussion were also included. Letters to the editor and conference proceedings were excluded.
