***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: We included 24 trials with 2996 participants in this updated review. The number of participants in each trial varied from 39 to 382. Most of the included studies compared bed rest versus immediate mobilization, and only two assessed the effects of supplementary fluids versus no supplementation. We judged the overall risk of bias of the included studies as low to unclear. The overall quality of evidence was low to moderate, downgraded because of the risk of bias assessment in most cases. The primary outcome in our review was the presence of PDPH. There was low quality evidence for an absence of benefits associated with bed rest compared with immediate mobilization on the incidence of severe PDPH (risk ratio (RR) 0.98; 95% confidence interval (CI) 0.68 to 1.41; participants = 1568; studies = 9) and moderate quality evidence on the incidence of any headache after lumbar puncture (RR 1.16; 95% CI 1.02 to 1.32; participants = 2477; studies = 18). Furthermore, bed rest probably increased PDPH (RR 1.24; 95% CI 1.04 to 1.48; participants = 1519; studies = 12) compared with immediate mobilization. An analysis restricted to the most methodologically rigorous trials (i.e. those with low risk of bias in allocation method, missing data and blinding of outcome assessment) gave similar results. There was low quality evidence for an absence of benefits associated with fluid supplementation on the incidence of severe PDPH (RR 0.67; 95% CI 0.26 to 1.73; participants = 100; studies = 1) and PDPH (RR 1; 95% CI 0.59 to 1.69; participants = 100; studies = 1), and moderate quality evidence on the incidence of any headache after lumbar puncture (RR 0.94; 95% CI 0.66 to 1.34; participants = 200; studies = 2). We did not expect other adverse events and did not assess them in this review. Since the previous version of this review, we found one new study for inclusion, but the conclusion remains unchanged. We considered the quality of the evidence for most of the outcomes assessed in this review to be low to moderate. As identified studies had shortcomings on aspects related to randomization and blinding of outcome assessment, we therefore downgraded the quality of the evidence. In general, there was no evidence suggesting that routine bed rest after dural puncture is beneficial for the prevention of PDPH onset. The role of fluid supplementation in the prevention of PDPH remains unclear.
Output:

This is an update of the original review published in 2013. We found one new study in a search of the published literature in February 2015. This review includes 24 studies with 2996 participants. We compared different types of bed rest and extra fluids to see if they prevented PDPH after a lumbar puncture. We found low to moderate quality evidence that bed rest does not prevent the onset of headaches after lumbar puncture, regardless of the duration of rest or the body or head positions assumed by the patient. Furthermore, bed rest probably increases the chances of having PDPH. We found few data on the usefulness of extra fluids, which did not seem to prevent PDPH. We believe that these practices should no longer be routinely recommended to patients for the prevention of headaches after lumbar puncture since there is no evidence supporting them. We considered the quality of the evidence for most of the outcomes assessed in this review to be low to moderate.