***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 eight cohort studies of which six were performed in primary care (total number of patients; n = 6622), one study was from an accident and emergency setting (n = 482), and one study was from a secondary care setting (n = 257). In the six primary care studies, the prevalence of spinal malignancy ranged from 0% to 0.66%. Overall, data from 20 index tests were extracted and presented, however only seven of these were evaluated by more than one study. Because of the limited number of studies and clinical heterogeneity, statistical pooling of diagnostic accuracy data was not performed. There was some evidence from individual studies that having a previous history of cancer meaningfully increases the probability of malignancy. Most "red flags" such as insidious onset, age > 50, and failure to improve after one month have high false positive rates. All of the tests were evaluated in isolation and no study presented data on a combination of positive tests to identify spinal malignancy. For most "red flags," there is insufficient evidence to provide recommendations regarding their diagnostic accuracy or usefulness for detecting spinal malignancy. The available evidence indicates that in patients with LBP, an indication of spinal malignancy should not be based on the results of one single "red flag" question. Further research to evaluate the performance of different combinations of tests is recommended.
Output:

Six family practice studies including over 6,600 back pain patients found 21 tumors (0.3%).  One study on back pain diagnosed in an emergency room and one on back pain in a spine clinic included 482 and 257 patients.  The family practice studies described 15 different questions and physical exam tests that have been used to screen for spinal tumors.  Most of the 15 were not accurate.  A previous history of cancer is a very useful indicator.  Other facts that may indicate cancer are age greater than 50, no prior history of back pain, and failure to improve after one month.  These are most likely useful when combined, or with other indicators such as a history of cancer.  By themselves, these three questions would result in over-testing of patients without cancer. The worst effects of low quality red flag screening are overtreatment and undertreatment.  If the tests are not accurate, patients without a tumor may get an x-ray, MRI, bone scan or CT scan that they don’t need—unnecessary exposure to x-rays, extra worry for the patient and extra cost.  At the other extreme (and much less common), it might be possible to miss a real tumor, and cause the patient to have extra time without the best treatment. Most of the studies were of low or moderate quality and did not use an MRI, the most accurate imaging test, to confirm the presence or absence of a tumor, so more research is needed to identify the best combination of questions and examination methods.