To describe the outcomes and associations of pericardial disease, with a particular focus on the outcomes of patients admitted with primary or secondary pericardial disease.

Retrospective observational study.

All public and private hospitals in New South Wales, Australia.

Hospitalised patients with pericardial disease admitted from 2004 to 2021 that was (a) a primary diagnosis or (b) a secondary diagnosis.

Mortality both in-hospital and during several years of available follow-up.

Out of 45 446 patients diagnosed with pericardial disease, under half (46.8%) had pericardial disease as the primary reason for hospitalisation. Patients in whom pericardial disease was the primary compared with the secondary diagnosis were more commonly male (68.2% vs 59.1%), younger (median 51.2 years vs 66.0 years) and less comorbid (age-adjusted median Charlson Comorbidity Index 1 vs 4). In patients with pericardial disease, adjusted in-hospital mortality was fivefold lower if this was the primary diagnosis (OR 0.21, p

Patients with pericardial disease have a low in-hospital mortality of about 1% if this was the primary diagnosis. However, patients in whom it was a secondary diagnosis, especially in the presence of comorbidities such as malignancy, had a much worse prognosis.

Many amputees experience phantom limb pain (PLP). Pharmacological management is the mainstay of treatment, but effectiveness is limited, and it is associated with significant side effects. Sensory discrimination training (SDT) is a non-pharmacological treatment for PLP. Previously, SDT required a clinician, or carer, to administer it, creating a barrier to real world use. In this trial, an automated SDT device (SP1X, 2pd Ltd, Middlesbrough, United Kingdom) for the self-management of PLP will be investigated for efficacy.

The Phantom Relief is a decentralised, randomised, placebo-controlled, mixed-methods, superiority trial. Participants will take part from their own homes, using an electronic data capture tool to complete all trial documentation. Eligible, consenting individuals with PLP (intensity rated as ≥4 on a 0–10 scale; n=100) will be randomised to receive the SP1X device (intervention group) or a placebo device SP1X7 (placebo group). The first and second treatment sessions will be observed via video call to provide set-up guidance and any additional advice needed. The primary outcome measure will be the McGill Pain Questionnaire revised (SF-MPQ-2). Outcome measures will be collected at baseline, 3 weeks (immediately post intervention) and 3 months follow-up. Statistical analysis will be carried out by a blinded statistician (analysis of covariance model conditioning on the baseline and stratification factors). Semi-structured interviews will be carried out with a sub-sample (n=10–15) of intervention group participants. Participants will be provided with their allocated device for home use. Online video calls will be used to instruct participants on how to set up and use the device by the research assistant (RA). The RA will observe the first and second treatment sessions and provide any additional advice needed. Participants in both groups will be asked to use the device for 60 min/day for at least 15 days of the 21-day treatment period and to record device use in a study diary.

Approval has been obtained from Teesside University School of Health and Life Sciences Research and Ethics Committee, the North of Scotland Research Ethics Service, Health Research Authority, and a letter of no objection was obtained from the Medicines and Healthcare products Regulatory Authority. The results will be disseminated through peer-reviewed articles, conference presentations and a doctoral thesis.

NCT04103983.