Interventions:
The interventions were described sufficiently and appear to have included the usual practice in the UK setting, but it was not clear if any other relevant comparators, such as the amylase test alone, should have been included. It is likely that these interventions were relevant for other settings.
Effectiveness/benefits:
The effectiveness data were well described and appear to come from a relevant source for the study population. The design of the study (a within-group comparison, in which each patient underwent both tests) allowed the intervention and comparator data to be collected from the same patients at the same time, which minimises bias. The sensitivity and specificity for each test alone were reported, but those for both tests together were not. The results may be generalisable to other similar settings. It was unclear whether the authors searched the published literature for other relevant data.
Costs:
The cost data consisted of one item, which was not well described. The authors did not explicitly state the study perspective and only considered the cost of measuring serum enzyme levels, which could indicate the perspective of a payer, but this still excluded a number of important cost categories, such as staff time, processing, and laboratory reporting. The source for the cost data was not referenced and it was unclear what price year the authors used. No sensitivity analysis was conducted.
Analysis and results:
A comparative analysis was appropriate to assess the relative costs and benefits of the two strategies. The impact of uncertainty was not evaluated, and uncertainty in the cost and outcome estimates might have affected the results. The reporting was adequate for the effectiveness data, but poor for the costs. The authors did not discuss the limitations of their analysis.
Concluding remarks:
Several aspects of the study were not well reported, especially the cost results, making it difficult to assess the authors' conclusions.