TABLE 1—
Model Input Parameters Used in Determining the Potential Cost-Effectiveness of School-Based Eating Disorder Screening
| Parameter | Mean Value (95% CI) | Statistical Distribution | Source |
| SCOFF, % | Cotton et al.22 | ||
| Sensitivity | 76 (62, 93) | Triangular | |
| Specificity | 88 (84, 93) | Triangular | |
| 12-mo prevalence of ED, % | National Comorbidity Survey, Swanson et al.1 | ||
| AN | 0.2 (0.10, 0.30) | Triangulara | |
| BN | 0.6 (0.29, 0.91) | Triangulara | |
| BED | 0.9 (0.59, 1.21) | Triangulara | |
| OSFED | 1.1 (0.86, 1.33) | Triangulara | |
| Probability of seeking clinical treatment (no screen), % | National Comorbidity Survey, Swanson et al.1 | ||
| AN | 27.5 (4.9, 50.1) | Triangulara | |
| BN | 21.5 (10.6, 32.4) | Triangulara | |
| BED | 11.4 (5.6, 17.2) | Triangulara | |
| OSFED | 3.4 (1.0, 5.8) | Triangulara | |
| Probability of full recovery from specified ED with therapy, % | Herzog et al.,23 Milos et al.,24 Lock et al.,25 Steinhausen26 | ||
| AN | 18.2 (7.2, 35.0) | Triangular | |
| BN | 23.9 (18.1, 29.7) | Triangular | |
| BEDc | 28.1 (25.4, 30.8) | Uniform | |
| Probability of partial recovery from specified ED with therapy, % | Milos et al.24 | ||
| AN | 13.4 (8.7, 17.9) | Uniform | |
| BN | 15.2 (11.9, 18.3) | Uniform | |
| BEDd | 14.2 (10.3, 18.1) | Uniform | |
| OSFED progression and recovery probability, % | Milos et al.24 | ||
| Progress from OSFED to AN with treatment | 11.4 (6.1, 16.9) | Uniform | |
| Progress from OSFED to BN with treatment | 12.8 (1.9, 23.5) | Uniform | |
| Progress from OSFED to BED with treatment | 20.7 (14.1, 27.3) | Uniform | |
| OSFED full recovery with treatment | 28.1 (25.4, 30.8) | Uniform | |
| Relative recovery probability without treatmentb | 50 (26, 74) | Uniform | Assumption |
| Probability of relapse with therapy, % | |||
| AN | Variese (NA) | Nonparametric | Strober et al.,27 Olmsted et al.,28 Birchall et al.29 |
| BN | Variese (NA) | Nonparametric | Herzog et al.,23 Grilo et al.,30 Keller et al.,31 Birchall et al.29 |
| AN or BN (sensitivity analysis) | Variese (NA) | Nonparametric | Wang et al.,32 Eddy et al.33 |
| BED or OSFED | 10.8 (NR) | NA | Milos et al.24 |
| Utility values (scale = 0–1) | |||
| AN | 0.72 (NR) | NA | Vos and Mathers34 |
| Recovered from AN | 0.91 (NR) | NA | de la Rie et al.35 |
| BN | 0.8 (NR) | NA | Pohjolainen et al.36 |
| Recovered from BN | 0.94 (NR) | NA | de la Rie et al.35 |
| BED or OSFED | 0.77 (NR) | NA | Grenon et al.37 |
| Recovered from BED or OSFED | 0.91 (NR) | NA | de la Rie et al.35 |
| Screening costs, $ | |||
| Cost per SCOFF instrument | 0.03 (0.01, 0.05) | Uniform | Assumption |
| Teachers’ hourly wage | 27.74 (NA) | NA | US National Compensation Survey38 |
| Cost of initial diagnostic consultation, $ | 134 (123, 144) | Normal | 2010 US Medical Expenditure Panel Survey39 |
| Cost of standard therapy, $ | Striegel-Moore et al.40 | ||
| AN | 11 375 (271, 65 818)f | Lognormal | |
| BN | 5 574 (207, 30 066)f | Lognormal | |
| BEDg | 6 035 (113, 36 715)f | Lognormal | |
| Cost of low-intensity therapy, $ | Striegel-Moore et al.40 | ||
| AN | 4 411 (160, 23 672)f | Lognormal | |
| BN | 3 541 (207, 17 167)f | Lognormal | |
| BED or OSFEDg | 2 977 (223, 13 310)f | Lognormal |
Note. AN = anorexia nervosa; BED = binge-eating disorder; BN = bulimia nervosa; CI = confidence interval; ED = eating disorder; NA = not applicable; NR = not reported; OSFED = other specified feeding or eating disorder. SCOFF is a self-administered, 5-question ED screening instrument.20,21 We inflated all costs to 2012 dollars using the medical care component of the Consumer Price Index.41
The primary source reported means and standard deviations for these estimates. We calculated the 95% confidence interval from these estimates assuming a normal distribution, and a triangular distribution was used in the model to avoid sampling negative probabilities in uncertainty analyses.
We assumed that without treatment, recovery rates would be 25% to 75% lower than recovery rates with treatment. This value was randomly sampled from a uniform distribution.
Derived from eating disorder not otherwise specified (ED-NOS) recovery probability.
Assumed to be the average of AN and BN partial recovery probabilities.
Probability varies on the basis of number of years of treatment received. In the base case analysis, AN and BN recovery probabilities ranged from 2.3% to 17.1% and 4.9% to 48.5%, respectively, over 10 years. In the sensitivity analysis, recovery probabilities were 0%, 19%, 29%, 40%, 43%, 47%, and 50% for the first 7 years of treatment, respectively, and 100% afterward.
A lognormal distribution was used to model the 95% confidence interval to represent the positively skewed distribution that is typical of cost data. The mean and standard deviation that were reported in the literature were transformed into the mean of logs and standard deviation of logs to simulate the lognormal distribution.42
Reported as ED-NOS in the original study. As BED was formerly part of ED-NOS,18 we used the same treatment costs for BED and OSFED.