Ryan 2009.

Study characteristics
Methods	Single centre, randomised controlled cross‐over study
Participants	Participants were individuals receiving ongoing warfarin therapy for > 2 months and who had internet access, and were able to use a home INR meter (n = 162).
Interventions	Self‐monitoring vs usual care Participants were randomised to supervised self‐testing or to usual care (conventional clinic management) for 6 months; subsequently the allocation was reversed for a further 6 months. In the self‐testing group, participants initially self‐tested INR twice weekly. Once the INR was therapeutic for 2‐3 consecutive readings, the interval between tests was increased to a maximum of every 2 weeks. Participants accessed a web‐based system to enter signs and symptoms and INR and receive instant automated guidance on dose and testing; if INR deviation was serious the participant was asked to take a bolus dose of warfarin (< 1.5) or hold their warfarin (> 5.0) and/or to log in later the same day for additional instructions. If a participant reported a symptom suggestive of a bleed or an embolus they were told to seek immediate medical advice. The research pharmacist accessed the caregiver interface of the program at least once daily to review participant problems. Any participant who failed to test their INR or log in to the program as scheduled was contacted by telephone the same day. All new dosage recommendations were reviewed and adjusted if necessary. All extreme INRs (<1.5 or >5.0) were discussed by the research pharmacist with a consultant haematologist. Participants attended the anticoagulation clinic every 2 months to give a venous blood sample for laboratory analysis of INR, which was compared with the self‐tested value. The comparison group received conventional clinic management.
Outcomes	Time to therapeutic range, proportion of participants within therapeutic range, testing frequency, number of extreme INRs recorded, participant satisfaction, thrombotic events, bleeding.
Trial identification
Study duration	12 months
Oral anticoagulant used	Warfarin
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated randomisation sequence
Allocation concealment (selection bias)	Low risk	Allocation implemented via sealed envelopes
Intention to treat analysis	High risk	ITT was not performed.
Reporting of losses of follow‐up	Low risk	30 participants (19%) withdrew; reasons reported
Blinding	High risk	Participants and study staff were not blind to the intervention allocation. It is not reported whether data analysts were blind to allocation.