Table 3 Description of measures evaluated by study participants

Medical Outcomes Study Short-Form 12 (SF-12)

A 12-item generic HRQOL measure derived from the SF-36 [31, 32]. There are 8 dimensions namely: (i) physical functioning (ii) physical role (iii) bodily pain (iv) general health (v) vitality (vi) social functioning (vii) emotional role (viii) mental health. These can be computed into 2 distinct clusters, PCS-12 and MCS-12 with higher values indicating better HRQOL [31].

EuroQOL 5-dimension (EQ-5D)

A utility measure with a self-classifier and a visual analogue scale (VAS) which can be used to value health states [33]. The self-classifier includes 5 dimensions: (i) mobility (ii) self-care (iii) usual activities (iv) pain/discomfort (v) anxiety/depression. Each dimension has 3 levels of severity (no problems, some problems, and severe problems) and it is possible to describe 243 health states between 0 (dead) and 1 (perfect health) [33].

Chronic Liver Disease Questionnaire (CLDQ)

A 29-item liver disease–specific HRQOL questionnaire with 6 dimensions [27] namely: (i) abdominal symptoms (ii) activity (iii) emotional function (iv) fatigue (v) systemic symptoms (vi) worry.

Summary scores for each domain range from 1 (most impairment) to 7 (least impairment).

Paediatric Quality of Life Inventory - Transplant Module version 3.0 (PedsQL-TM 3.0)

A 46-item transplant specific module of the PedsQL questionnaire [34] with 8 dimensions namely: 1) about my medicines I (barriers to medical regimen adherence), 2) about my medicines II (medication side effects), 3) my transplant and others (social relationships and transplant), 4) pain and hurt (physical discomfort), 5) worry (worries related to health status), 6) treatment anxiety (fears regarding medical procedures), 7) how I look (impact of transplant on appearance), and 8) communication (communication with medical personnel and others regarding transplant issues) [34].

A 5-point response scale is utilized Items are reverse-scored and linearly transformed to a 0 to 100 scale (0 = 100, 1 = 75, 2 = 50, 3 = 25, 4 = 0) with higher scores indicating better HRQOL [35].