***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: Three eligible trials involving 569 patients were identified. Due to methodological limitations in the included studies, there was considerable variation in the results of acute (risk range 38.67% to 96.51%) and chronic pain (risk range 7.83% to 40.47%) across the control groups. Therefore, meta-analysis was not performed but the results of the outcomes in the individual trials were compared. Two trials involving 322 patients reported less chronic pain after preperitoneal repair (relative risk (RR) 0.18, number needed to treat (NNT) 8; RR 0.51, NNT 5), whereas one trial, including 247 patients, described more chronic pain after this repair (RR 1.17, NNT 77). The same trials favoured the preperitoneal technique concerning acute pain (RR 0.17, NNT 3; RR 0.78, NNT 7), whereas in the third trial it was almost omnipresent and thus comparable in both intervention arms (RR 0.997, NNT 333). Early and late hernia recurrence rates were similar across the studies, whereas contrasting results were reported for other early outcomes as infection and hematoma. No late mesh infection occurred in the included trials.  Both techniques are valid as they result in similar low recurrence rates. Evaluation of pain results in the individual trials shows some evidence that preperitoneal repair causes less or comparable acute and chronic pain compared to the Lichtenstein procedure. We emphasize the need for homogeneous high quality randomized trials comparing elective preperitoneal inguinal hernia techniques and Lichtenstein repair in terms of chronic pain.
Output:

The review authors identified three eligible controlled trials in which 569 patients were randomized to Lichtenstein or preperitoneal mesh repair. Due to methodological limitations in the included trials, the data were not pooled. Comparison of pain results in the individual trials showed that preperitoneal repair causes less chronic pain (relative risk (RR) 0.18, number needed to treat (NNT) 8; RR 0.51, NNT 5) compared to the Lichtenstein procedure in two trials involving 322 patients. One trial, including 247 patients, described more chronic pain after this repair (RR 1.17, NNT 77). The same trials favoured the preperitoneal technique concerning acute pain (RR 0.17, NNT 3; RR 0.78, NNT 7), whereas in the third trial it was almost omnipresent and thus comparable in both intervention arms (RR 0.997, NNT 333). This method also showed similar low recurrence rates after both types of repair. The results for other early complications were not consistent across the included trials. No mesh infections were reported. In conclusion, both techniques are valid causing few recurrences. Analysis of pain results in each trial shows some evidence that preperitoneal repair causes less or comparable acute and chronic pain compared to the Lichtenstein technique. As no robust conclusions concerning chronic pain after elective hernia surgery can be made, we highlight the need for homogeneous trials.