Table 1. Parameter inputs used in the economic analysis.
Baseline characteristics of children | ||||||
Mean | SE | Distribution | Lower bound | Upper bound | Source (references) | |
Proportion male | 87.57% | 1.47% | Beta-bionomial | 84.69% | 90.45% | IPD Meta-analysis |
Proportion with intellectual disability (IQ<70) | 82.95% | 3.32% | Beta-bionomial | 57.32% | 61.55% | IPD Meta-analysis |
Age in months | 36 | 0 | NA | NA | NA | Assumption |
Adaptive behaviour (VABS) | 63.19 | 0.43 | Beta-bionomial | 62.35 | 64.04 | IPD Meta-analysis |
Cognitive ability (IQ) | 59.43 | 1.08 | Beta-bionomial | 57.32 | 61.55 | IPD Meta-analysis |
Autism symptom severity (ADOS) | 6.98 | 0.18 | Beta-bionomial | 6.63 | 7.33 | IPD Meta-analysis |
Natural history | ||||||
Mean | SE | Distribution | Lower bound | Upper bound | Source | |
Adaptive behaviour (VABs) * | —0.45 | 1.27 | Normal | -2.94 | 2.04 | [31–34] |
Cognitive ability * | -0.28 | 1.24 | Normal | -2.70 | 2.14 | |
Short-term treatment effect year 1 | ||||||
Mean | SE | Distribution | Lower bound | Upper bound | Source | |
Adaptive behaviour (VABs) * | 2.92 | 2.46 | Normal | -1.90 | 7.76 | IPD Meta-analysis |
Cognitive ability (IQ) * | 9.16 | 2.44 | Normal | 4.38 | 13.93 | |
Short-term treatment effect year 2 | ||||||
Mean | SE | Distribution | Lower bound | Upper bound | Source | |
Adaptive behaviour(VABs) * | 7.00 | 2.58 | Normal | 1.95 | 12.06 | IPD Meta-analysis |
Cognitive ability (IQ) * | 14.13 | 2.54 | Normal | 9.16 | 19.10 | |
Education type regression coefficients Primary school | ||||||
Coefficient | SE | Distribution | Lower bound | Upper bound | Source | |
Adaptive behaviour (VABs) | -0.08 | 0.02 | Normal | -0.12 | -0.042 | [34, 35] |
Cognitive ability (IQ) | -.02 | 0.01 | Normal | -0.051 | 0.006 | |
Cut 1 (mainstream with support) | -8.75 | 0.02 | Normal | -11.08 | -6.42 | |
Cut 2 (specialist schooling) | -6.10 | 0.86 | Normal | -7.781 | -4.41 | |
Education type regression coefficients Secondary school | ||||||
Coefficient | SE | Distribution | Lower bound | Upper bound | Source | |
Adaptive behaviour (VABs) | -0.04 | 0.02 | Normal | -12.48 | -6.27 | [36] |
Cognitive ability (IQ) | -0.06 | 0.02 | Normal | -9.32 | -3.89 | |
Cut 1 (mainstream with support) | -9.37 | 1.58 | Normal | -0.084 | -0.001 | |
Cut 2 (specialist schooling) | -6.60 | 1.39 | Normal | -0.089 | -0.025 | |
Educational placement based (observed values applied in scenario analysis only) | ||||||
Coefficient | SE | Distribution | Lower bound | Upper bound | Source | |
Mainstream (ABA) | 30% | N/A | N/A | N/A | N/A | [10, 34, 35] |
Mainstream with support (ABA) | 38% | N/A | N/A | N/A | N/A | |
Special education (ABA) | 32% | N/A | N/A | N/A | N/A | |
Mainstream (TAU) | 1% | N/A | N/A | N/A | N/A | |
Mainstream with support (TAU) | 27% | N/A | N/A | N/A | N/A | |
Special education (TAU) | 72% | N/A | N/A | N/A | N/A | |
Regression model used to predict quality of life in Children | ||||||
Coefficient | SE | Distribution | Lower bound | Upper bound | Source | |
Constant | −0.2438 | 0.2015 | Beta-bionomial | -0.639 | 0.154 | [37] |
Age | 0.0119 | 0.0186 | Beta-bionomial | -0.025 | 0.048 | |
Age2 | 0.0003 | 0.0010 | Beta-bionomial | -0.002 | 0.001 | |
ADOS score | -0.0063 | 0.0078 | Beta-bionomial | 0.0071 | 0.013 | |
Cognitive ability (IQ; Log) | 0.0304 | 0.0478 | Beta-bionomial | -0.063 | 0.124 | |
Adaptive behaviour (VABs) | 0.0103 | 0.0016 | Beta-bionomial | -0.021 | 0.009 | |
Costs of interventions | ||||||
Mean | SE | Distribution | Lower bound | Upper bound | Source | |
ABA-based interventions | £36,682.78 | £7,336 | Gamma | £22,303 | £51,062 | Micro-costed [38, 39] |
TAU | £8,634.33 | £1,726 | Gamma | £5,249 | £12,019 | Assumption/personnel communication. |
Social care and medical costs | ||||||
Coefficient | SE | Distribution | Lower bound | Upper bound | Source | |
Intercept | £1,900.09 | £762.41 | Normal | $405. | £3394 | [36] |
Adaptive behaviour (VABs) | -£8.78 | £13.98 | Normal | -£36.18 | £18.63 | |
Cognitive ability (IQ) | -£7.81 | £10.99 | Normal | -£29.35 | £13.74 | |
Costs of Schooling | ||||||
Mean | SE | Distribution | Lower bound | Upper bound | Source | |
Mainstream School | £4,417.70 | £883 | Gamma | £2,686 | £6,149 | [36] |
Supported | £8,689.78 | £1,737 | Gamma | £5,283 | £12,096 | |
Special School | £15,702.78 | £3,140 | Gamma | £9,547 | £21,858 | |
Adult care costs | ||||||
Mean | SE | Distribution | Lower bound | Upper bound | Source | |
Own home/parents | £0.00 | NA | NA | NA | NA | [38, 40] |
Sheltered -Low intensity | £53,274.88 | £10,654.98 | Gamma | £32,391 | £74,159 | |
Sheltered—High intensity | £99,336.44 | £19,867.29 | Gamma | £60,397 | £13,8276 | |
Residential | £115,553.00 | £23,110.60 | Gamma | £70,256 | £16,0850 | |
Day services | £17,728.57 | £3,545.71 | Gamma | £10,779 | £24,678 | |
Respite care | £1,927.00 | £385.40 | Gamma | £1,172 | £2,682 | |
Employment support | £290.00 | £58.00 | Gamma | £176 | £404 | |
Adult education | £4,159.00 | £831.80 | Gamma | £2529 | 5789.328 | |
Hospital | £43.00 | £8.60 | Gamma | £26.14 | 59.86 | |
Other health and social services | £726.00 | £145.20 | Gamma | £441 | £1,010 |
ABA = Applied Behaviour Analysis, ADOS = Autism Diagnostic Observation Schedule, IQ = intelligence quotient, SE = Standard error, TAU = Treatment as Usual, VABs = Vineland Adaptive Behavior Scales
* Annual changes in scores