Study designs of evaluations included in the review
The designs of the included studies were not stated in the review.
Specific interventions included in the review
Studies using the paracetamol absorption test to assess gastric emptying were eligible for inclusion. The rate at which paracetamol appeared in the blood was taken to reflect the rate of gastric emptying. The doses of paracetamol were 1 or 1.5 g, or 20 mg/kg, given with various combinations of meals. Articles in the review also used area under the curve, fixed-time concentrations, concentration-max, or time-to-concentration-max as the parameter of paracetamol absorption.
Reference standard test against which the new test was compared
The reference standard test used in this review was scintigraphy. Studies were excluded when the paracetamol absorption test was not compared directly with the scintigraphic method.
Participants included in the review
The inclusion criteria for the participants were not specified a priori. The included participants were adults aged between 19 and 75 years. Further details of the participants were reported in the article.
Outcomes assessed in the review
The correlation coefficient between scintigraphy and a parameter of paracetamol absorption was used as the main outcome measure. The correlation was considered satisfactory if it was 0.60 or more, moderate between 0.45 and 0.60, and poor if below 0.45. Studies were excluded if they did not report sufficient correlation data. Clinical feasibility was assessed by studying the administration of paracetamol, frequency of blood sampling, duration of the test period, and parameters used in the analysis.
How were decisions on the relevance of primary studies made?
The authors do not state how the papers were selected for the review, or how many of the reviewers performed the selection.