Utility scores are generated using the time-trade off approach where the responses to the five items are valued based on general population valuation scores.
These states may then be converted into a single index value by applying published reference weights (for CoBalT, the UK population valuation set [ 16]) to each domain response and subtracting the total of these weights from one [ 2].
In general, the designs could be differentiated in terms of the type of health states, selection of study population, valuation task etc. Health states were divided into hypothetical states and actual states.
Injured population valuations are higher (better-rated health) than general population valuations for all 13 health states considered except 11111 (no problems on any EQ-5D dimension).
Which EQ-5D dimensions are most strongly associated with the population valuations is also investigated.
To our knowledge, no studies comparing patient and general population valuations include data for New Zealand.
The one exception to the finding that injured population valuations exceed general population valuations is the valuation for state 11111: it is lower for the injured population than for the general population.
An advantage of a general population sample is that, because of the widespread use of utilities derived from general population valuations, scores derived via this approach are comparable to general population valuations of other health states.
