In medical studies, the efficacy of medical treatments (called interventions) is evaluated within a group of study participants. You will be given a sentence of a study report in which your task is to list the phrases that describe the intervention(s) of the study. You should list the phrase in the same order that they appear in the text, separated by commas. If no information about the interventions is mentioned, just answer with "not found". Interventions are: a specific drug, surgery, talking therapy, a lifestyle modification, control or placebo treatment. Do not include details, dosages, frequency and duration, intervention mentions that are not in an informative span of text.
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Question: Previous analyses that focused on health care underestimated this economic burden , particularly for school systems .

Answer: not found


Question: Limitations and suggestions for future research are discussed .

Answer: not found


Question: The comparative results were very close ; mean difference ( bias ) +/- standard deviation ( precision ) was 0.05 ( 0.84 ) mmol/min/kPa .

Answer:
not found