Microcosting and Resource-Use Valuation

Definition and scope

Cost estimation that identifies resource quantities and assigns unit values at an explicit level of detail, keeping measurement of resource use separate from valuation and perspective. The target population, use, and analysis remain protocol decisions; this card explains the choices and their consequences rather than approving a study.

Operational specification

Specify intervention components, staff categories, time, consumables, facilities, capital, overhead, opportunity costs, and the allocation of shared capacity. Record quantity sources, unit-price sources, price year, currency, and whether the unit cost already includes overhead or other bundled elements.

Analysis and diagnostics

Calculate quantity times unit cost at the resource level, aggregate only after reconciling units and avoiding double counting, and propagate uncertainty in quantities and prices. Compare top-down and bottom-up alternatives where they could change the decision. Use observed workflows or validated records rather than replacing missing activities with invented averages.

When NOT to use and common errors

A billed charge is not automatically a resource cost. Adding a bundled tariff to separately priced components can double count. Unused staff time is not always a cash saving when a service is reduced, and a highly detailed calculation can still have a wrong perspective.

Worked example and implementation boundary

A synthetic visit uses 0.5 staff hours valued at 60 per hour, supplies costing 12, and allocated room cost 8. No listed component is bundled into another. The illustrative visit resource cost is 50 currency units. It is a resource valuation, not necessarily the billed or paid amount. The code performs that explicitly stated calculation with synthetic inputs. It is not a complete fitted analysis and does not demonstrate the identification assumptions, estimate sampling uncertainty, or certify application in another population.

Data-source and reporting requirements

Preserve the provenance, dates, units, and observation rule for each input. Claims capture services and transactions under observable benefits; absence of a record is not proof that an event or resource use did not occur. EHR and registry measurements depend on the collection process and may miss care outside the system. Linked sources add reconciliation and selection questions. Primary collection can improve a missing domain but still requires valid measurement and follow-up. Report which of these limitations affects the stated use, which evidence supports the chosen inputs, and what remains uncertain.

Worked example

Scenario

A synthetic visit uses 0.5 staff hours valued at 60 per hour, supplies costing 12, and allocated room cost 8. No listed component is bundled into another.

Dataset

Synthetic inputs with units defined in the scenario; no patient data.

Steps

Result

The illustrative visit resource cost is 50 currency units. It is a resource valuation, not necessarily the billed or paid amount.

Trade-offs

Code example

hours = 0.5
hourly_value = 60
supplies = 12
room = 8
result = hours*hourly_value+supplies+room
assert abs(result - 50.0) < 1e-9
print(result)

hours <- 0.5
hourly_value <- 60
supplies <- 12
room <- 8
result <- hours*hourly_value+supplies+room
stopifnot(abs(result - 50.0) < 1e-9)
print(result)

Citations

1. [1]Husereau D, et al. Consolidated Health Economic Evaluation Reporting Standards (CHEERS) 2022 Explanation and Elaboration: A Report of the ISPOR CHEERS II Good Practices Task Force. Value in Health. 2022.
2. [2]Ramsey SD, Willke RJ, Glick H, et al. Cost-effectiveness analysis alongside clinical trials II — an ISPOR Good Research Practices Task Force report. Value in Health. 2015;18(2):161-172.