As anticipated, there was a higher degree of missing data in the anxiety domain from the self-completed group.
In the EORTC QLQ-CR29, several changes have been made with the aim of reducing missing data in the sexual domain.
There were a low percentage of missing data in these specific domains, all below 4.0%% but one in appearance concern domain (6.5 %).
Questionnaires with missing data were kept, but domains of the heiQ-Fv with one or more missing items were rejected.
Many RCTs had missing data especially on the domains of sequence generation, allocation concealment and blinding.
The only deficits contributing to missing data were from the social domain.
The relatively large proportion of missing data in the sexual functioning domain could have resulted in a lack of power to show differences.
In accordance with developer instructions, if missing data for a SF-36 domain was ≤ 50% then data were imputed using the mean of participants' responses to the completed items [ 29].
24 To decrease bias and increase statistical efficiency, we imputed missing data for quality of life domain scores, interrupter resistance measurements, duration of hospital stay, height, and presence of thrush.
Because of missing data on some of the domains, the number of patients with PCS and MCS scores was 136.
