Table 3 Quality assessment of economic evaluations according to the Drummond checklist

Study Design

Was the research question stated?

Yes

Yes

Yes

Yes

Yes

Was the economic importance of the research question stated?

No

Partially

Partially

Yes

Partially

Was the viewpoint of the analysis clearly stated and justified?

Yes, but not justified

Yes, but not justified

Yes, but not justified

Not clearly stated, not justified

Yes, but not justified

Was a rationale reported for the choice of the alternative programmes or interventions compared?

N/A

N/A

N/A

N/A

N/A

Were the alternatives being compared clearly described?

Yes

Yes

Yes

Yes

Yes

Was the form of economic evaluation stated?

Yes

Yes

Yes

No

Yes

Was the choice of form of economic evaluation justified in relation to the questions addressed?

No

Yes

Yes

No

Yes

Data Collection

Were the sources of effectiveness estimates used stated?

Yes

Yes

Yes

Yes

Yes

Were details of the design and results of the effectiveness study given?

Yes

Yes

Yes

Yes

Yes

Were the primary outcome measures for the economic evaluation clearly stated?

Yes

Yes

Yes

Yes

Yes

Were the methods used to value health states and other benefits stated?

No

Yes

Yes

Partially

No

Were the details of the subjects from whom valuations were obtained given?

No

No

No

Partially (only age)

No

Were productivity changes (if included) reported separately?

Not stated

N/A

Not stated

N/A

Not stated

Was the relevance of productivity changes to the study question discussed?

No

N/A

No

N/A

No

Were quantities of resources reported separately from their unit cost?

No

No

No

No

No

Were the methods for the estimation of quantities and unit costs described?

No

No

No

No

No

Were currency and price data recoded?

Yes (aggregate prices)

Yes (aggregate prices)

Yes (aggregate prices)

Yes (aggregate prices)

Currency yes; price data only for MHT

Were details of price adjustments for inflation or currency conversion given?

Yes, for inflation. Prices from other countries used. No, for currency conversion

Yes, for inflation. No other currency used

Yes, for inflation. Prices from other countries used. No, for currency conversion

No

Yes, for inflation. No other currency used

Were details of any model used given?

Yes

Yes

Yes

N/A

Yes

Was there justification for the choice of model used and the key parameters on which it was based?

Yes for model. Partially for parameters

Partially for model & for parameters

Yes for model. Partially for parameters

N/A

Partially for the model. Yes for parameters

Analysis & Interpretation

Was time horizon of cost and benefits stated?

Yes

Yes

Yes

Yes

Yes

Was the discount rate stated?

Yes

Yes

Yes

Yes

Yes

Was the choice of rate justified?

No

No

No

No

No

Was an explanation given if cost or benefits were not discounted?

Both were discounted

Both were discounted

Both were discounted

No, benefits not discounted

Not clear what was discounted

Were the details of statistical tests and confidence intervals given for stochastic data?

Standard deviations given for QALYs

No

No

No

No

Was the approach to sensitivity analysis described?

Yes

Yes

Yes

Yes

Yes

Was the choice of variables for sensitivity analysis described?

Yes

Yes

Yes

Yes

listed only in results table

Were the ranges over which the parameters were varied stated?

Yes

Yes

Yes

Yes

Yes

Were relevant alternatives compared?

Yes

Yes

Yes

Yes

Yes

Was an incremental analysis reported?

Yes

Yes

Yes

Yes

Yes

Were major outcomes presented in a disaggregated as well as aggregated form?

Yes

No

No

No

Yes

Was the answer to the study question given?

Yes

Yes

Yes

Yes

Yes

Did conclusions follow from the data reported?

Yes

Yes

Yes

Yes

Yes

Were conclusions accompanied by the appropriate caveats

Partially

Partially

Partially

Partially

Partially

Were generalisability issues addressed?

Partially

Partially

Partially

Partially

Partially