A systematic review and economic model of the effectiveness and ...

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Review of economic evaluations of ADHD drug interventions in children and adolescents
TABLE 84 Cost-effectiveness results from cost–utility model submitted by Eli Lilly
Subgroup MPH QALYs: strategy Cost: strategy QALYs: strategy Cost: strategy ICER (£)
with ATX with ATX (£) without ATX without ATX (£)
1 ER 0.9341 599.78 0.9140 334.07 13,241
1 IR 0.9308 534.09 0.9040 125.76 15,224
2 NA 0.9217 480.94 0.8800 0.00 11,523
3 NA 0.9268 488.26 0.8967 39.48 14,945
4 NA 0.9120 395.98 0.8800 0.00 12,370
5 ER 0.9331 595.32 0.9126 316.32 13,609
5 IR 0.93 531.52 0.9033 121.49 15,355
NA, not applicable.
assess the quality of the methodology or the
suitability of the sample of parents from whom the
valuations were elicited. The sample consisted of
parents of children with ADHD, and so the
current treatment of their children could
potentially introduce bias into the results. As such,
the results of this utility elicitation study should be
interpreted with caution.
Summary of cost-effectiveness
The submission states that owing to the use of
patient-level simulation, a probabilistic sensitivity
analysis was not practical, and so the model is run
deterministically. As a result, the model cannot
provide an estimate of the uncertainty around the
estimated costs and effects. The cost-effectiveness
results are shown in Table 84. Subgroups 1 and 5
are associated with two sets of results because the
treatment strategies include MPH, of which there
are two formulations, extended and instant
release.
No detail is given of the pseudo-standard errors
one would expect from a patient-level simulation,
so it is not possible to judge whether enough
patients were simulated to ensure stable estimates.
The two pair-wise comparisons in subgroups 1 and
5 can be reduced to one four-way comparison by
computing the ICERs using the rules of
dominance and extended dominance (see p. 95).
Using this method, the use of ER-MPH without
ATX is ruled out by extended dominance in both
subgroups. The ICER for IR-MPH with ATX
compared with IR-MPH without ATX is £15,236 in
subgroup 1 and £15,357 in subgroup 2 and the
ICER for ER-MPH with ATX compared with IR-
MPH with ATX is £19,906 in subgroup 1 and
£20,581 in subgroup 2.
Several one-way sensitivity analyses were
conducted. As expected, the results of the model
were affected predominately by the utility values
used.
Comments on methodology
As the electronic model was not submitted within
the time frame for this review, it was not possible
to verify or clarify further the information
provided in the submission. It is also not possible
to re-analyse the model for any further sensitivity
analyses. The use of ATX is shown to be costeffective,
this result being driven by the utility
values employed and the assumptions regarding
the persistence of side-effects. Like the others, the
submission did not consider long-term effects of
medication for ADHD. Without examining the
electronic model, the need for a patient-level
simulation rather than cohort structure is unclear.