Inclusion Criteria:  Ability to give informed consent Adults aged 18 years and above, with no upper age limit Prescribed any opioid analgesic (defined as any opioid or opioid/paracetamol combination analgesic from sections 4.7.2 and 4.7.1 British National Formulary) for non-cancer pain for a period of ≥3 months (defined as ≥ 2 opioid prescriptions issued in the previous 3 months with a minimum interval of 60 days between the first and last prescription)  Exclusion Criteria:  Cancer pain Terminal illness Vulnerable patients (e.g. severe mental illness, learning difficulties, dementia, care home residents) Unable to understand English Deemed by their GP to be inappropriate to contact