An Implementation Science Approach to Evaluating Self-Administered Acupressure for Knee Osteoarthritis in Older-Aged Adults in the Community

Inclusion Criteria: 1. ethnic Chinese; 2. aged 60 years or above; 3. able to read Chinese and comprehend Mandarin or Cantonese; 4. fulfilling any 3 of the following criteria. i. morning stiffness 30 min; ii. crepitus on active joint motion; iii. bone tenderness; iv. bone enlargement; or v. no palpable joint warmth (this classification on those with age \>50 years yielded 84% sensitivity, and 89% specificity for OA knee diagnosis (25)); 5. having knee pain for at least 3 months (26); 6. knee pain 23 on a Likert pain scale from 1-10; 7. having a smartphone (or a family member living together having a smartphone) that is compatible with WhatsApp (based on our previous studies, almost every eligible subject is used to using WhatsApp for social communication); and 8. willing to provide informed consent. Exclusion Criteria: 1. medical diagnoses or conditions that preclude individuals from active participation (e.g., bleeding disorders, alcohol, or drug abuse); 2. knee pain related to other conditions (cancer, fracture, rheumatoid arthritis, and rheumatism) as screened according to the red flags for further investigation or referral in the NICE 2014 Guidelines for Osteoarthritis of the knee (27); 3. score \< 22 in Hong Kong Montreal Cognitive Assessment (HK-MoCA) indicating cognitive impairment that may prevent the understanding of training instructions (28); 4. body mass index over 30, the obese Il criteria for Asians (29) (obese subjects will find great difficulty in performing acupressure on acupoints because physical pressure reaching the muscle is required); and 5. ever had knee-replacement surgery Further investigation or referral, either at the screening or during the study, will be made whenever necessary.