Background: Nasal polyps cause nasal obstruction, discharge and reduction in or loss of sense of smell, but their aetiology is unknown. The management of chronic rhinosinusitis with nasal polyps, aimed at improving these symptoms, includes both surgical and medical treatments, but there is no universally accepted management protocol.

Objectives: To assess the effectiveness of endonasal/endoscopic surgery versus medical treatment in chronic rhinosinusitis with nasal polyps.

Search methods: We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the search was 20 February 2014.

Selection criteria: Randomised controlled trials of any surgical intervention (e.g. polypectomy, endoscopic sinus surgery) versus any medical treatment (e.g. intranasal and/or systemic steroids), including placebo, in adult patients with chronic rhinosinusitis with nasal polyps.

Data collection and analysis: We used the standard methodological procedures expected by The Cochrane Collaboration. Meta-analysis was not possible due to the heterogeneity of the studies and the selective (incomplete) outcome reporting by the studies.

Main results: 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.

Authors' conclusions: 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.

Joanne Rimmer has no conflicts of interest to declare.

Wytske Fokkens has no conflicts of interest to declare.

Lee Yee Chong has no conflicts of interest to declare.

Claire Hopkins has no conflicts of interest to declare.