Table 2.
Proposed variables and data sources for WS2
| Variable | Type of variable | Proposed measure | Source | Timings of data collection (months) | ||
| 0 | 9 | 18 | ||||
| Participant characteristics/predictors | ||||||
| Age | Predictor | Date of birth | Parent | √ | ||
| Ethnicity | Census groups | Parent | √ | |||
| Deprivation | Index of Multiple Deprivation (based on postcode) | Parent | √ | √ | √ | |
| Parental educational attainment | Census groups | Parent | √ | |||
| Household composition | Number of children, marital/living status | Parent | √ | √ | √ | |
| Diagnosis | Paediatrician | √ | ||||
| Comorbidities | Paediatrician | √ | √ | √ | ||
| All medications | Paediatrician | √ | √ | √ | ||
| Complexity | Disability Complexity Scale23 24 | Paediatrician | √ | √ | √ | |
| Length of time gastrostomy fed at T0 | Months/years | Parent | √ | |||
| Comparator | ||||||
| Diet: formula/blended | Main grouping variable | Parent | √ | √ | √ | |
| Outcomes | ||||||
| Nutritional content of feeds | Outcome | Commercial for formula | Dietitian/parent | √ | √ | √ |
| myfood2415 | Parent | √ | √ | √ | ||
| Anthropometric data | Outcome | Height or length Weight Triceps skinfold thickness or mid-arm circumference |
Dietician Paediatrician |
√ | √ | √ |
| Gastrointestinal symptoms | Outcome | PedsQL gastrointestinal19 | Parent/child | √ | √ | √ |
| Child quality of life | Outcome | PedsQL generic module18 | Parent/child | √ | √ | √ |
| Parental quality of life | Outcome | EQ-5D-5L25
Parenting Morale Index26 |
Parent | √ | √ | √ |
| Healthcare use | Outcome | Client service receipt inventory27 | Parent | √ | √ | √ |
| Outcome | Number of hospital admissions Number of accident and emergency (A&E) attendances |
HES data | √ | √ | √ | |
| Safety | Outcome | Tube blockages Number of stoma infections Number of gastrointestinal infections |
Parent | |||
| Outcome | Number of hospital admissions and A&E attendance associated with child’s gastrostomy/diet | HES and parent | √ | √ | √ | |
| Family resource use | Outcome | Time preparing feeds; impact on other caring/parenting Financial costs |
Parent | √ | √ | √ |
| Non-staff NHS resource use | Outcome | Cost of formula and packaging Dietetic resources |
Dietitian | √ | √ | √ |
EQ-5D-5L, 5-level version of EuroQol-5 Dimension; HES, Hospital Episodes Statistics; NHS, National Health Service; PedsQL, Pediatric Quality of Life Inventory; WS2, workstream 2.