Table A2.

Additional GHCC Reference Case Recommendations (Costs) and VAWG Guidelines.

GHCC Recommendations (Adapted with permission from: https://ghcosting.org/pages/standards/reference_case)	VAWG Guidelines
2. The perspective of the cost estimation should be defined.	We recommend transparency in perspective. The analyst should declare if the economic evaluation takes the perspective of the NGO provider or the health sector.
3. The type of unit cost estimated should be defined in terms of economic versus financial, real-world versus normative best practice, and full versus incremental cost, and whether the cost is net of future cost savings. The type of cost should be justified relevant to purpose.	We recommend the estimation of real-world full economic costs of developing and delivering the intervention and, where relevant, its “usual care” comparator. We do not recommend computing future cost savings, due to the uncertainty surrounding estimates of costs to society of VAWG.
4. The “units” in the unit costs for strategies, services, and interventions should be defined, relevant for the costing purpose, and generalizable.	We identify units relevant to a range of programs and settings (see Table 3). We recommend unit costs relevant to the type of program and setting be estimated and reported.
6. The scope of the inputs to include in the cost estimation should be defined and justified relevant to purpose. Where inputs are excluded for pragmatic reasons, these should be reported.	To identify all relevant inputs, and exclude all inputs that are not relevant, we recommend analysts compile a detailed description of inputs for the intervention development, adaptation, and implementation phases. For a template, see the intervention description workbook attached to our guidelines, downloadable from the project resources pages of the What Works? Program: https://bit.ly/2vKaGZZ
7. The methods for estimating the quantities of inputs should be described, including methods, data sources, and criteria for allocating shared costs, and the exclusion of research costs.	Studies should implement a bottom-up approach based on micro-costing for direct costs. For overhead and support costs, a top-down approach based on micro-costing is deemed acceptable, if micro-costs are not available (for definitions, see our guidelines at https://bit.ly/2vKaGZZ).
8. The sampling frame, method, and size should be determined by the precision demanded by the costing purpose and designed to minimize bias.	VAWG prevention efforts often rely on high numbers of staff and volunteers. We therefore recommend sampling a subset of sites to capture variation in service delivery. This ensures the sample is representative of the different settings where the intervention is delivered and that the data can be used in modeling scale-up analyses.
9. The selection of the data source and methods for estimating “units” for unit costs should be described, with potential biases reported in the study limitations.	We recommend identifying relevant units for unit costs based on a review of the literature in the intervention’s specific field, in the first instance. However, where publications are scarce, we also recommend interviewing implementation managers and developers to identify useful units not included in the literature.
10. Consideration should be given to the timing of data collection to minimize recall bias and, where relevant, the impact of seasonality and other differences over time.	We advise prospective data collection. However, where this is not feasible due to project timetable constraints, we advise that retrospective data collection takes place as soon as possible after end of delivery.
11. The sources for price data should reflect the price relevant to purpose and be described for each input in a way that allows for adjustment across settings.	We recommend analysts report the sources for each price used.
12. Capital costs should be appropriately amortized or depreciated to reflect the expected life of capital inputs	Capital costs are first expressed in real prices at the base year and then annuitized based on their expected life using standard tables (see, for example, Drummond et al., 2014).
13. Where relevant, appropriate discount, inflation, and currency conversion rates should be used and clearly stated.	Base case: We recommend the use of a standard 3% discount rate, the use of the GDP deflator as an inflation index, and the use of market exchange rates to convert currencies. Sensitivity analyses: Local discount rates, market exchange rates adjusted for PPA rates to take differences in price levels into account; “VAWG”-specific PPP and substitution of local prices with prices from other localities, where comparisons are being made.
14. The use and source of shadow prices, for goods where no market price exists, and for the opportunity cost of time should be reported.	Base case: We recommend the use of replacement costs as a pragmatic option in the absence of market prices. Data sources should be clearly identified and documented in the tools. Sensitivity analysis: The opportunity cost of using specific resources is computed, and sources reported.
15. Variation in the cost of the intervention by site size/organization, sub-populations, or by other drivers of heterogeneity should be explored and reported.	We recommend analysts collect cost data with sufficient variation in geography, size, and platform type to analyze how these key cost drivers may affect overall intervention cost. The cost-effectiveness analysis should report on pre-specified sub-populations (for trials), and on sub-populations likely to differ substantially from the average in terms of costs and/or cost-effectiveness (also see iDSI Principle 8).

Note. This table contains a summary of our guidance for conducting economic evaluations of VAWG prevention and women’s empowerment interventions in low- and middle-income countries. The reader is encouraged to refer to the main body of the article for in-depth explanations. Our accompanying costing guidelines (at https://bit.ly/2vKaGZZ), the iDSI Reference Case and the GHCC Reference Case websites offer further insights into the concepts referred in table. GHCC = Global Health Costing Consortium; VAWG = violence against women and girls; NGO = nongovernmental organization; GDP = gross domestic product; PPA = purchasing power adjusted; PPP = purchasing power parity; iDSI = International Decision Support Initiative.