An Observational Study of Diagnostic Criteria, Clinical Features and Management of Opioid-induced Constipation (OIC) in Patients With Cancer Pain

StOIC-1 is an observational study, and will involve a single visit (see below for schedule).

The following data will be collected: a) demographic data - age, gender, ethnicity; b) cancer diagnosis; c) opioid medications - drug, formulation, dose; d) laxative medications - drug, formulation, dose; e) other medications; f) Eastern Co-operative Oncology Group performance status

The participants will be asked the following questions:

1. Simple question - "Are you constipated?" [Options - yes / no / unsure]
2. European Association for Palliative Care definition question - "Does the following question describe your bowel function: 'the passage of small, hard faeces infrequently and with difficulty?' [Options - yes / no / unsure]
3. Camilleri definition question - "Does the following statement describe your bowel function: 'a change since initiating opioid therapy from baseline bowel habits that is characterised by any of the following: reduced bowel movement frequency, development or worsening of straining to pass bowel movements, a sense of incomplete rectal evacuation, harder stool consistency?' [Options - yes / no / unsure
4. Rome IV diagnostic criteria for OIC

The participants will also be asked to complete: