Background
Methods
Model structure
Intervention
Physical activity level
Base case value | Lower limit | Upper limit | Distribution for PSA | Source | |
---|---|---|---|---|---|
Starting age | 45 | 25 | 65 | Normal | GIAG |
Proportion of recruited participants completing the programme | 15.5 % | 1 % | 50 % | Beta | GIAG |
Baseline activity level-all recruited participants | |||||
Low | 32.4 % | – | – | Dirichlet | GIAG |
Moderate | 37.6 % | 25 % | 50 % | Dirichlet | GIAG |
High | 30.0 % | 15 % | 50 % | Dirichlet | GIAG |
Follow-up activity level-completers | |||||
Low | 23.5 % | – | – | Dirichlet | GIAG |
Moderate | 23.5 % | 10 % | 40 % | Dirichlet | GIAG |
High | 52.9 % | 35 % | 65 % | Dirichlet | GIAG |
Duration of effect of Give it a Go on PA (months) | 12 | 4 | 20 | Uniform | Assumption |
Relative risks of coronary heart disease | |||||
Moderate activity level | 0.90 | 0.83 | 0.99 | Lognormal | [1] |
High activity level | 0.81 | 0.68 | 0.96 | Lognormal | [1] |
Relative risks of stroke | |||||
Moderate activity level | 0.86 | 0.79 | 0.93 | Lognormal | [3] |
High activity level | 0.74 | 0.64 | 0.85 | Lognormal | [3] |
Relative risks of type II diabetes | |||||
Moderate activity level | 0.67 | 0.53 | 0.84 | Lognormal | [2] |
High activity level | 0.61 | 0.41 | 0.9 | Lognormal | [2] |
Relative risk for mortality | |||||
Non CVD mortality after CHD | 1.71 | 1.44 | 1.98 | Lognormal | [14] |
CVD mortality after CHD | 3.89 | 3.81 | 3.97 | Lognormal | [14] |
Non CVD mortality after stroke | 1.71 | 1.44 | 1.98 | Lognormal | [14] |
CVD mortality after stroke | 3.89 | 3.81 | 3.97 | Lognormal | [14] |
Non CVD mortality after diabetes | 1.49 | 1.24 | 1.74 | Lognormal | [15] |
CVD mortality after diabetes | 2.61 | 2.34 | 2.88 | Lognormal | [15] |
Utilities | |||||
CHD 1st event | 0.80 | 0.622 | 0.931 | Beta | [6] |
Post CHD first event | 0.92 | 0.665 | 1.000 | Beta | [6] |
Stroke 1st event | 0.63 | 0.503 | 0.749 | Beta | [6] |
Post stroke 1st event | 0.65 | 0.518 | 0.771 | Beta | [6] |
Diabetes | 0.90 | 0.665 | 0.997 | Beta | [6] |
Mental health gain when moderately active | 0.023 | 0.000 | 0.200 | Beta | [8] |
Mental health gain when highly active | 0.104 | 0.000 | 0.200 | Beta | [8] |
Base case value | Lower limit | Upper limit | Distribution for PSA | |
---|---|---|---|---|
Incidence rates (yearly) | ||||
CHD 33–34 | 0.0035 % | 0.0017 % | 0.0059 % | Beta |
CHD 35–44 | 0.0465 % | 0.0391 % | 0.0546 % | Beta |
CHD 45–54 | 0.2095 % | 0.1933 % | 0.2263 % | Beta |
CHD 55–65 | 0.6310 % | 0.6028 % | 0.6599 % | Beta |
CHD 65–74 | 0.9700 % | 0.9350 % | 1.0056 % | Beta |
CHD 75–81 | 0.9700 % | 0.9350 % | 1.0056 % | Beta |
Stroke 33–34 | 0.0080 % | 0.0035 % | 0.0142 % | Beta |
Stroke 35–44 | 0.0230 % | 0.0148 % | 0.0330 % | Beta |
Stroke 45–54 | 0.0570 % | 0.0435 % | 0.0723 % | Beta |
Stroke 55–65 | 0.2910 % | 0.2593 % | 0.3245 % | Beta |
Stroke 65–74 | 0.6900 % | 0.6408 % | 0.7410 % | Beta |
Stroke 75–81 | 1.4340 % | 1.3630 % | 1.5068 % | Beta |
Diabetes 33–39 | 0.0090 % | 0.0077 % | 0.0104 % | Beta |
Diabetes 40–49 | 0.0280 % | 0.0257 % | 0.0305 % | Beta |
Diabetes 50–59 | 0.0632 % | 0.0596 % | 0.0669 % | Beta |
Diabetes 60–69 | 0.1005 % | 0.0959 % | 0.1051 % | Beta |
Diabetes 70–79 | 0.1116 % | 0.1068 % | 0.1164 % | Beta |
Diabetes 80–81 | 0.1116 % | 0.1068 % | 0.1164 % | Beta |
Probability of event being fatal | ||||
CHD fatal 33–34 | 8.77 % | 7.130 % | 10.566 % | Beta |
CHD fatal 35–44 | 8.77 % | 7.130 % | 10.566 % | Beta |
CHD fatal 45–54 | 8.77 % | 7.130 % | 10.566 % | Beta |
CHD fatal 55–65 | 11.55 % | 9.386 % | 13.910 % | Beta |
CHD fatal 65–74 | 21.07 % | 17.087 % | 25.336 % | Beta |
CHD fatal 75–81 | 14.76 % | 11.988 % | 17.769 % | Beta |
Stroke fatal 33–34 | 23.46 % | 19.024 % | 28.212 % | Beta |
Stroke fatal 35–44 | 23.46 % | 19.024 % | 28.212 % | Beta |
Stroke fatal 45–54 | 23.46 % | 19.024 % | 28.212 % | Beta |
Stroke fatal 55–65 | 23.28 % | 18.876 % | 27.991 % | Beta |
Stroke fatal 65–74 | 23.47 % | 19.026 % | 28.215 % | Beta |
Stroke fatal 75–81 | 23.42 % | 18.989 % | 28.160 % | Beta |
Utility weights in low activity but healthy population | ||||
Age 33–44 | 0.90 | 0.880 | 0.919 | Beta |
Age 45–54 | 0.86 | 0.840 | 0.879 | Beta |
Age 55–64 | 0.82 | 0.800 | 0.839 | Beta |
Age 65–74 | 0.78 | 0.760 | 0.799 | Beta |
Age 75+ | 0.72 | 0.700 | 0.739 | Beta |
Disease risk
Quality of life
Costs
Base case value | Lower limit | Upper limit | Distribution for PSA | Source | |
---|---|---|---|---|---|
GIAG general - per person recruited | £38 | £10 | £100 | Gamma | GIAG |
GIAG leisure - per completer | £97 | £50 | £150 | Gamma | GIAG |
GIAG leisure - per non-completera
| £17 | £5 | £50 | Gamma | GIAG |
CHD 1st event | £4,144 | £3,372 | £4,995 | Gamma | [6] |
Post CHD first event, per year | £473 | £385 | £571 | Gamma | [6] |
Stroke 1st event | £10,698 | £8,704 | £12,894 | Gamma | [6] |
Post stroke 1st event, per year | £2,350 | £1,912 | £2,832 | Gamma | [6] |
Diabetes, per year | £955 | £777 | £1,152 | Gamma | [6] |
Model outputs and sensitivity analysis
Results
Base case
Total costs (95 % CI) | Total life-years (95 % CI) | Total QALYs (95 % CI) | Incremental costs per QALY gained (95 % CI) | |
---|---|---|---|---|
No intervention | £2,287 (1,428–3,312) | 19.235 (16.233–21.758) | 16.370 (13.255–19.325) | – |
Give it a Go | £2,354 (1,495–3,374) | 19.235 (16.234–21.758) | 16.373 (13.257–19.328) | – |
Increment | £67.25 (48–90) | 0.0001 (0.0000–0.0002) | 0.0033 (0.0002–0.0106) | £20,347 (513–35,119) |
One-way sensitivity analysis
Base case value | Threshold valuea
| |
---|---|---|
Starting age | 45 | 55 |
Proportion of recruited participants completing the programme | 15.5 % | 15.8 % |
Baseline activity level-all recruited participants | ||
Moderate | 37.6 % | 36.1 % |
High | 30.0 % | 29.7 % |
Follow-up activity level-completers | ||
Moderate | 23.5 % | 25.0 % |
High | 52.9 % | 53.3 % |
Duration of effect of Give it a Go on PA (months) | 12 | 13 |
Utilities | ||
Mental health gain when moderately active | 0.023 | 0.021 |
Mental health gain when highly active | 0.104 | 0.106 |
Costs | ||
GIAG general-per person recruited | £38.30 | £37.15 |
GIAG leisure-per completer | £97.00 | £89.60 |
GIAG leisure-per non-completer | £16.75 | £15.39 |