Abstract: Four studies (231 participants randomised) are included in the review. No studies were at low risk of bias. The studies compared different types of surgery versus various types and doses of systemic and topical steroids and antibiotics. There were three comparison pairs: (1) endoscopic sinus surgery (ESS) versus systemic steroids (one study, n = 109), (2) polypectomy versus systemic steroids (two studies, n = 87); (3) ESS plus topical steroid versus antibiotics plus high-dose topical steroid (one study, n = 35). All participants also received topical steroids but doses and types were the same between the treatment arms of each study, except for the study using antibiotics. In that study, the medical treatment arm had higher doses than the surgical arm. In two of the studies, the authors failed to report the outcomes of interest. Although there were important differences in the types of treatments and comparisons used in these studies, the results were similar. Primary outcomes: symptom scores and quality of life scores There were no important differences between groups in either the patient-reported disease-specific symptom scores or the health-related quality of life scores. Two studies (one comparing ESS plus topical steroid versus antibiotics plus high-dose topical steroid, the other ESS versus systemic steroids) failed to find a difference in generic health-related quality of life scores. The quality of this evidence is low or very low. Endoscopic scores and other secondary outcomes Two studies reported endoscopic scores. One study (ESS versus systemic steroids) reported a large, significant effect size in the surgical group, with a mean difference (MD) in score of -1.5 (95% confidence interval (CI) -1.78 to -1.22, n = 95) on a scale of 0 to 3 (0 = no polyposis, 3 = severe polyposis). In the other study (ESS plus topical steroid versus antibiotics plus high-dose topical steroid) no difference was found between the groups (MD 2.3%, 95% CI -17.4% to 12.8%, n = 34). None of the included studies reported recurrence rates. No differences were found for any objective measurements or olfactory tests in those studies in which they were measured. Complications Complication rates were not reported in all studies, but rates of up to 21% for medical treatment and 14.3% for surgical treatment are described. Epistaxis was the most commonly reported complication with both medical and surgical treatments, with severe complications reported rarely. The evidence relating to the effectiveness of different types of surgery versus medical treatment for adults with chronic rhinosinusitis with nasal polyps is of very low quality. The evidence does not show that one treatment is better than another in terms of patient-reported symptom scores and quality of life measurements. The one positive finding from amongst the several studies examining a number of different comparisons must be treated with appropriate caution, in particular when the clinical significance of the measure is uncertain. As the overall evidence is of very low quality (serious methodological limitations, reporting bias, indirectness and imprecision) and insufficient to draw firm conclusions, further research to investigate this problem, which has significant implications for quality of life and healthcare service usage, is justified.

Plain-language summary: Four randomised controlled trials, involving a total of 231 patients with chronic rhinosinusitis with nasal polyps, are included in this review. The number of patients in each study ranged from 34 to 109. The studies took place in ENT departments in several European countries. All patients were adults and most of the studies enrolled more men than women. In all studies the patients were randomly assigned to either surgery or medical treatment (such as antibiotics or steroid tablets or injections) in addition to topical steroids given as nasal sprays or drops. Both the type of surgery performed and the medical treatments used varied widely between the studies, and did not allow all of the studies to be looked at together. Rather, we considered the treatment groups in the four studies as three separate pairs of comparisons instead of simply 'surgical' versus 'medical' treatments. The main outcome measures were patient-reported disease-specific symptom scores and health-related quality of life scores, as well as generic health-related quality of life scores. There were no important differences between groups in either the patient-reported disease-specific symptom scores or the health-related quality of life scores. Two studies (one comparing ESS plus topical steroid versus antibiotics plus high-dose topical steroid, the other ESS versus systemic steroids) did not find a difference in general health-related quality of life scores. Two studies reported changes in polyp size (when looked at with an endoscope) using a score. One study (ESS versus systemic steroids) reported a significantly better score in the surgery group than in the steroids group at 12 months. In the other study (ESS plus topical steroid versus antibiotics plus high-dose topical steroid) no difference was found between the groups. There were no reported differences between the different medical and surgical treatment groups in any study for any other objective (clinician-based) measurements. Complication rates were not reported in all studies, but nosebleeds (epistaxis) were the most commonly described complication with both medical and surgical treatment; severe complications were reported rarely in either group. The evidence does not show that one treatment is better than another in terms of patient-reported symptom scores and quality of life measurements. One positive finding (polyps size scores) from amongst the several studies examining a number of different comparisons must be treated with appropriate caution, in particular when the clinical significance of the measure is uncertain. There is not enough evidence to draw firm conclusions regarding the most appropriate treatment for this condition. Chronic rhinosinusitis with nasal polyps has significant implications for quality of life and the use of healthcare services. Further research to investigate this problem is justified. Overall, we found this evidence to be of low or very low quality. We have low confidence in the estimates of these studies; further research will very likely change these estimates. There were serious limitations in how the studies were carried out or reported (or both), and the number of participants involved was small. In addition, some of the treatment regimens used in the trials are no longer current standards of therapy for patients with chronic rhinosinusitis with nasal polyps. This evidence is up to date to 20 February 2014.