Detailed statistical analysis plan for the Danish Palliative care trial (DanPaCT)

• Main Authors: Johnsen, Anna T, Petersen, Morten A, Gluud, Christian, Lindschou, Jane, Fayers, Peter, Sjøgren, Per, Pedersen, Lise, Neergaard, Mette A, Vejlgaard, Tove Bahn, Damkier, Anette, Nielsen, Jan B, Strömgren, Annette S, Higginson, Irene J, Groenvold, Mogens
• Format: Article
• Language: English

Background Advanced cancer patients experience considerable symptoms, problems, and needs. Early referral of these patients to specialized palliative care (SPC) could offer improvements. The Danish Palliative Care Trial (DanPaCT) investigates whether patients with metastatic cancer will benefit from being referred to ‘early SPC’. DanPaCT is a multicenter, parallel-group, superiority clinical trial with 1:1 randomization. The planned sample size was 300 patients. The primary data collection for DanPaCT is finished. To prevent outcome reporting bias, selective reporting, and data-driven results, we present a detailed statistical analysis plan (SAP) for DanPaCT here. Results This SAP provides detailed descriptions of the statistical analyses of the primary and secondary outcomes in DanPaCT. The primary outcome is the change in the patient’s ‘primary need’. The ‘primary need’ is a patient-individualised outcome representing the score of the symptom or problem that had the highest intensity out of seven at baseline assessed with the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). Secondary outcomes are the seven scales that are represented in the primary outcome, but each scale evaluated individually for all patients, and survival. The detailed description includes chosen significance levels, models for multiple imputations, sensitivity analyses and blinding. In addition, we discuss the patient-individualized primary outcome, blinding, missing data, multiplicity and the risk of bias. Conclusions Only few trials have investigated the effects of SPC. To our knowledge DanPaCT is the first trial to investigate screening based ‘early SPC’ for patients with metastatic cancer from a broad spectrum of cancer diagnosis.