Verteporfin photodynamic therapy for neovascular age-related ...

116 Appendix 1level of benefit from treatment. The proposed study will measure both SRVF(NEIVFQ [4]) and generic QoL (SF-36 [5]). Defining the relationships betweenchanges in clinical measures of vision and SRVF/QoL is a specified secondaryobjective of the study, allowing the average reduction in QoL experienced by AMDpatients per unit of MDVA or CS lost to be estimated. Questionnaires will beadministered 6 monthly.9.5 Resource useAs described above, a questionnaire will be administered to patients every 6 months(as part of the extended dataset) to ask patients about the costs and consequencesto them of having the treatment and about their use of resources in other agencies(e.g. GP, district nurse) relating to the intervention. Treatment resources used will beidentified from the number of treatments given (documented in the database) andfrom observation of the resources used in providing treatment in a number of DPs.When measuring the total costs of the intervention, the resources used in providingthe intervention will be recorded separately from the unit costs. The review performedfor the NICE appraisal found that cost-utility estimates for PDT could be influencedby the number of treatments and that the same benefits as found in the existing trialsof PDT might be achieved at lower costs. In particular, the frequency of re-treatmentin routine practice, which may be a key component of costs, may differ from a clinicaltrials setting. The review also suggested additional resources might be needed toimplement the intervention at each DP which have been ignored in previous costutility analyses. The resources used in setting up the service will be recorded by sitevisitsto several of the DPs, chosen to reflect differences in clinical practice. Inaddition to the costs of providing the intervention to the health service, the resourcesused by patients and their carers in accessing the service will be recorded andcompared indirectly with the resource use for untreated patients (see 10.4).9.6 Morphological changes in lesionsThese secondary outcomes will be estimated from angiographic evidence of changein total lesion size, total CNV leakage, classic leakage and fibrosis. Note, theseparameters will be used for analysis and should not be confused with the lesionfeatures that determine eligibility and re-treatment (see section 4).