50 subjects with moderate knee osteoarthritis were supplied for four weeks with two tablets/day, each containing 350 mg of standardized extracts of Zingiber officinale and Acmella oleracea.

Subjects were supplied for four weeks with two tablets/day and there was the evaluation of pain intensity, by a 30-days Visual Analogue Scale (VAS) and b) the assessment of knee function by Western Ontario and McMaster Universities Arthritis Index and by Tegner Lysholm Knee Scoring collected at baseline, at 15 and 30 days after treatment, Health-related quality of life, by the ShortForm36, inflammation by C-reactive protein and Erythrocyte Sedimentation Rate, body composition by dual-energy X-ray absorptiometry measured at baseline and 30 days after treatment.

Pain intensity measured both at motion and at rest, using the Visual Analogue Scale (VAS). VAS measures a characteristic or attitude ranging across a continuum of values and cannot be directly measured. For example, the amount of pain that a patient feels ranges across a continuum from none to an extreme amount of pain. The VAS score is determined by measuring in millimeters from the left hand end of the line to the point that the patient marks. The results are showed with a scale 0-10. 0 means no pain and 10 high pain.

Assessment of knee pain by WOMAC (Western Ontario and McMaster Universities Arthritis) Index. The WOMAC pain scale consists of five questions that assess pain while walking on a flat surface, going up or down stairs, in bed at night, sitting or lying, and standing upright. The responses are recorded on a five-point Likert scale, with a higher score representing a greater level of pain. This scale is valid and reliable in hip and knee OA populations.

Tegner Lysholm Knee function Scoring (TLKS). Each patient completed a self-report questionnaire, TLKS, related to knee symptoms and function. It includes eight items: Limp, Support, Locking, Instability, Pain, Swelling, Stair climbing and Squatting. Each possible response to the items gives an arbitrary score on an increasing scale with a maximum of 100, a higher score representing a higher ability.

Health-related quality of life, recorded by the Short Form 36 Health questionnaire (SF-36), a generic measure of health status designed for use in population surveys which consider body pain as a dimension of health status. This is a self-reporting questionnaire and outcomes are measured with 8 numbers that express 8 different aspects of quality of life. Scoring 36-Item Health Survey is a two-step process. First, precoded numeric values are recoded per the given scoring key. all items are scored so that a high score defines a more favorable health state. In addition, each item is scored on a 0 to 100 range so that the lowest and highest possible scores are 0 and 100, respectively. Scores represent the percentage of total possible score achieved. In step 2, items in the same scale are averaged together to create the 8 scale scores. Hence, scale scores represent the average for all items in the scale that the respondent answered.