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: At present no study of gastric dysrhythmia , measured with epigastric impedance , has been presented , and the purpose of the present study was to investigate gastric rhythms by means of impedance gastrography in control infants , compared to infants with different gastrointestinal diseases , before and after treatment of their disease .

Answer: not found


Question: One third were nonsmokers .

Answer: not found


Question: In accordance , calcium bioavailability in adolescents did not vary between the diets ( % WD = 40.4 +/- 5.1 , BD % = 38.2 +/- 3.6 ) .

Answer:
not found