Oral Health Impact Profile - German Version (OHIP-G 49) The original English version of the questionnaire was developed by Slade and Spencer (1994). The German translation and validation of the instrument was performed by John et al. (2002). The OHIP-G 49 contains 49 items that address specific problems of oral health, e.g., "problems with chewing of food" or "pain in the gums". Each item is assessed on a five-point scale (0: never to 4: very often). A sum score of all of the items is calculated as an indicator for current oral health. The completion of the questionnaire takes about ten minutes.