***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: Only three trials, involving 189 participants, satisfied the inclusion criteria and these were of low methodological quality. One study showed a significant difference in hearing recovery in the vasodilator group (carbogen combined with a course of several other drugs) compared to the control group (a course of several other drugs alone). Another study only showed a significant improvement in higher frequencies in the vasodilator group (prostaglandin E1 + steroid) compared with the control group (placebo and steroid), no difference having been shown in overall hearing gain. In the third study the vasodilator group (naftidrofuryl and low-molecular weight dextran) showed an improvement only in lower frequencies over the control group (placebo and low-molecular weight dextran). Two of the studies reported adverse effects from vasodilator treatment, whereas there was no mention of any side effects in the third. Five patients in one study developed a sensation of heaviness in the head which settled spontaneously and did not interfere with treatment. In the other study one patient developed an allergic reaction and had to be excluded from the study. The effectiveness of vasodilators in the treatment of ISSHL remains unproven. The included studies were of relatively poor quality and the number of patients included was small. Moreover, there were differences in the type, dosage and duration of vasodilator used in each study. Due to the degree of heterogeneity the results could not be combined to reach a conclusion.
Output:

We found three trials, involving 189 participants, which showed improvement in hearing thresholds in those treated with vasodilators compared to control groups. However, as the number of patients included in the studies was small, and there were differences in the type, dosage and duration of vasodilator treatment used in each of these studies, the results could not be combined to reach a conclusion. The effectiveness of vasodilators in the treatment of ISSHL could not be proven. Further research is needed.