CRITICAL APPRAISALS

Critical Appraisals

Glasziou, et al., 2010

Muntinga, et al., 2012

  1. Was a well-defined question posed in answerable form?

The objective of the study is to determine how cost effective it is to administer a fixed dose combination of perindopril and indapamide to patients with type 2 diabetes mellitus. The study does not, however, frame this objective in a question form. The study then proceeds to provide a background of the need to reduce vascular complications in patients with type 2 diabetes.

The study focuses on the challenges that occur when delivering care to older adults. The aim of the study is not in a question format but rather the researchers have framed it as an experiment as to whether the challenges in giving care to older adults can be addressed by introducing the geriatric care model.

  1. Was a comprehensive description of the competing alternatives given?

The study presents two different methods used to reduce vascular complications in patients suffering from type 2 diabetes. On one hand, there is the traditional strategy that set blood pressure targets for treatment while on the other hand there is the BP lowering therapy which can be done by a fixed dose combination of perindopril and indapamide.

The study acknowledges the challenges in delivering care to older adults and then suggests the introduction of the geriatric care model which is based on the chronic care model to address the challenges. The purpose of the research is not to cover the different approaches to deal with the challenges but rather to evaluate the effectiveness of the care model to the quality of life of older adults in community dwellings.

  1. Was (How will) the effectiveness of the programmes or services (be) established?

The results of the study revealed that the cost-effectiveness of the use of a fixed dose combination of perindopril and indapamide was A$49 200 for every premature death that was prevented. This cost is considered acceptable and is within the cost of other interventions. The cost was lower than the cost of the traditional strategies of setting BP targets which required intensive resources due to frequent patient visits.

The study is an outline of the research to be conducted to test the effectiveness of the geriatric care model. The effectiveness of the model will be established by conducting a 2-year randomised clinical trial where the chronic care model is to be compared to the normal care.

  1. Were all the important and relevant costs and consequences for each alternative identified?

Cannot tell.

The authors have identified the total costs for general practitioner visits and the perindopril and indapamide drugs per month in table 1. It is difficult to ascertain whether this cost covers both the traditional strategy of setting BP targets and the new one suggested by the authors.

The study is an outline of research that is conducted. The authors outline the ways that the costs of introducing geriatric care model will be calculated, but the specific costs are not well outlined until the actual research is done.

  1. Were costs and consequences measured accurately in appropriate physical units prior to valuation?

The authors used market prices to estimate the cost of drugs and also used the average charges for general practitioner visits. The authors then use this information to show how the costs of the drugs translate to lowering the BP of the patients hence reducing mortality and improving the quality of life of the patients.

The authors present a proposed study hence the actual costs and consequences of the research have not yet been evaluated. The study, however, describes the process that will be used to measure the costs and evaluate the consequences.

  1. Were (Will) costs and consequences (be) valued credibly?

The cost of the drug strategy was analysed from the health care purchaser’s perspective and all the direct costs considered. Further, consequences such as the quality of life were measured for each patient which shows credibility.

The authors state that all the direct and indirect costs of the care model will be considered in the economic evaluation. Further, the Dutch standards costs will be used to value the use of resources. This shows a credible valuation of costs and consequences.

  1. Were (Will) costs and consequences (be) adjusted for differential timing?

Cannot tell.

There is no mention of any change in costs or the consequences where there is a difference in timing. Further, the fact that the research was conducted at the same time means that adjustments for differential timing were not made.

The authors state that the use of the stepped-wedge design in the study is supposed to ensure that differences between changes in outcomes due to time and due to intervention are considered.

  1. Was (Will) in the incremental analysis of costs and consequences of alternatives (be) performed?

Although the research provides a discussion on the traditional strategy to lowering BP and the proposed strategy consisting of the use of perindopril and indapamide drugs, there is no clear data to show differences in costs between the alternatives.

The scope of the research is restricted to the costs and consequences of the introduction of geriatric care model as a way to address the challenges in providing care to older adults. The study will not cover the incremental analysis of any alternative.

  1. Was (Will) uncertainty in the estimates of costs and consequences (be) adequately characterised?

The authors used the non-parametric bootstrap process to estimate and analyse the uncertainty in the estimated results in costs and consequences. Further, a sensitivity analysis was also used to measure the effect of uncertainty on the main results.

Cannot tell.

Given the fact that the research has not been conducted, some of the details of the research are not so clear. However, the authors have stated that uncertainty in the results is to be measured by the percentile bootstrapping method.

  1. Did (Will) the presentation and discussion of study results include all issues of concern to users

The focus of the research was to test the cost-effectiveness of the use of perindopril and indapamide drugs in lowering BP for patients with type 2 diabetes. The results covered the cost of the procedure and its ability to improve the quality of life.

The researchers intend to introduce geriatric care model in the delivery of care to older adults to evaluate its effect on the quality of life of the older adults and also measure the cost-effectiveness of the model. The proposal for the research contains a detailed process to ensure that these factors are considered.

References

Glasziou, P., Clarke, P., Alexander, J., Rajmokan, M., Beller, E., Woodward, M., Chalmers, J., Poulter, Neil. & Patel, A. (2010). Cost-effectiveness of lowering blood pressure with a fixed combination of perindopril and indapamide in type 2 diabetes mellitus: An advance trial-based analysis. Medical Journal of Australia, 193(6), 320-324.

Muntinga, M., Hoogendijk, E., Leeuwen, K., Hout, H., Twisk, J., Van der Horst, H., Nijpels, G. & Jansen, A. (2012). Implementing the chronic care model for frail older adults in the Netherlands: Study protocol of ACT (frail older adults: Care in transition). Biomed Central Geriatrics, 12(19), 1-10.