The Cancer Home Life Intervention Study Protocol: Effectiveness on Everyday Activities and Quality of Life in People With Advanced Cancer Living at Home. A Randomised, Controlled Multicentre Trial and a Health Economic Evaluation

The sample size is based on the primary outcome measure: the mean Activty of Daily Living (ADL) motor ability 1.04 logits (SD 0.727) as measured by the Assessment of Motor and Process Skills (AMPS). A significance level of 0.05 would provide 80% power to detect a between-group difference of 0.3 logits requiring a sample size of N=184. An expected drop-out rate of 32% at 3 months follow-up means that 272 patients with advanced cancer must be included in the study from three hospitals.

Multiple imputation will be used to estimate a plausible value for missing data of participants that are lost to follow-up due to other reasons than death. This does not, however, apply to the primary outcome data where no estimations will be computed.

For normally distributed ratio data the intervention group will be compared with the control group using multiple linear regression analysis of mean changes from baseline. Logistic regression analysis will be used for ordinal data. Adjustments for hospital and for baseline values will be made. A modified intention-to-treat analysis will be applied. Subgroup analyses to identifiy groups that especially benefit from the intervetnion will be performed.

The cost-effectiveness analysis wil be performed with ADL motor ability as the clinical parameter, and the cost-utility analysis will be based on the calculation of Quality Adjusted Life Years (QALY). The Incremental Cost-effectiveness Ratio (ICER) will be calculated and the results summarised in a cost-effectiveness acceptability curve (CEAC).