***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 identified five RCTs including 663 patients with one to four brain metastases. The risk of bias associated with lack of blinding was high and impacted to a greater or lesser extent on the quality of evidence for all of the outcomes. Adding upfront WBRT decreased the relative risk of any intracranial disease progression at one year by 53% (RR 0.47, 95% CI 0.34 to 0.66, P value < 0.0001, I2 =34%, Chi2 P value = 0.21, low quality evidence) but there was no clear evidence of a difference in  OS (HR 1.11, 95% CI 0.83 to 1.48, P value = 0.47, I2 = 52%, Chi2 P value = 0.08, low quality evidence) and PFS (HR 0.76, 95% CI 0.53 to 1.10, P value = 0.14, I2 = 16%, Chi2 P value = 0.28, low quality evidence). Subgroup analyses showed that the effects on overall survival were similar regardless of types of focal therapy used, number of brain metastases, dose and sequence of WBRT. The evaluation of the impact of upfront WBRT on NF, HRQL and neurological adverse events was limited by the unclear and high risk of reporting, performance and detection bias, and inconsistency in the instruments and methods used to measure and report results across studies. There is low quality evidence that adding upfront WBRT to surgery or SRS decreases any intracranial disease progression at one year. There was no clear evidence of an effect on overall and progression free survival. The impact of upfront WBRT on neurocognitive function, health related quality of life and neurological adverse events was undetermined due to the high risk of performance and detection bias, and inconsistency in the instruments and methods used to measure and report results across studies
Output:

We included five studies. These studies reported the effect of adding whole brain radiation to surgery or radiosurgery in terms of survival, brain disease progression, quality of life and treatment side effects. The sample size of these studies ranged from 19 to 359 patients. Adding whole brain radiotherapy to surgery or radiosurgery reduces brain metastases progression rates substantially but there was no clear evidence of an effect on survival and it is unclear whether it may cause side effects such as memory loss. We considered the evidence on survival, intracranial disease progression, neurocognitive function, quality of life and treatment side effects to be of low quality.