| Omentoplasty for oesophagogastrostomy after oesophagectomy |
| Omentoplasty for the prevention of anastomotic leakage after colonic or rectal resection |
| Omission of whole breast irradiation for postmenopausal women with early breast cancer |
| On screen point of care computer reminders to improve care and health |
| On the road: farewelling Elaine Beller |
| On-site mental health workers delivering psychological therapy and psychosocial interventions to patients in primary care: effects on the professional practice of primary care providers |
| Once daily long-acting beta2-agonists and long-acting muscarinic antagonists in a combined inhaler versus placebo for COPD |
| Once versus twice daily injections of low molecular weight heparin for the initial treatment of blood clots in the veins |
| Once-daily LABA/ICS combined inhalers versus inhaled long-acting beta2-agonists for people with chronic obstructive pulmonary disease |
| Oncoplastic breast-conserving surgery (O-BCS) for women with primary breast cancer |
| One site versus two site phacotrabeculectomy for primary open angle glaucoma |
| One study shows promise for Personal Assistance delivered to adults with physical impairments: more research is needed |
| One study supports use of Personal Assistance for children and teens with intellectual impairments: more research is needed |
| One topical fluoride (toothpastes, or mouthrinses, or gels, or varnishes) versus another for preventing dental caries in children and adolescents |
| One well-controlled study shows some evidence of effect of two interventions for childhood apraxia of speech (CAS) |
| One, two or three times a week iron supplements for improving health and development among children under 12 years of age |
| One-incision versus two-incision surgical techniques for anterior cruciate ligament reconstruction in adults |
| One-step techniques for primary distal hypospadias in children and adolescents |
| One-to-one oral hygiene advice for oral health |
| Online support groups for women with breast cancer |
| Online- and local area network (LAN)-based eLearning interventions for medical doctors' education |
| Oocyte activation for women following intracytoplasmic sperm injection (ICSI) |
| Open Dialogue for psychosis or severe mental illness |
| Open general medical wards versus specialist psychiatric units for acute psychoses |
| Open minimally invasive versus video-assisted minimally invasive parathyroidectomy for primary hyperparathyroidism |
| Open release for carpal tunnel syndrome |
| Open retropubic colposuspension for urinary incontinence in women |
| Open surgery using mesh for groin hernia repair |
| Open surgical procedures for incisional hernias. |
| Open versus closed surgical exposure of eye teeth that are displaced in the roof of the mouth |
| Open versus laparoscopic approach to pouch surgery in patients with ulcerative colitis and familial adenomatous polyposis showed no significant differences in mortality and complications, but the laparoscopic approach resulted in better cosmesis. |
| Open versus laparoscopic repair for paediatric inguinal hernia |
| Open, small-incision, and laparoscopic cholecystectomy seem comparable with regard to mortality and complications |
| Operational Criteria Checklist for Psychotic Illness and Affective Illness (OPCRIT+) for diagnosing schizophrenia in people with psychotic symptoms |
| Operative technique for the treatment of popliteal artery aneurysms |
| Operative versus conservative management for 'fetal distress' in labour |
| Opiods for restless legs syndrome |
| Opioid agonist maintenance for opioid dependent patients in prison |
| Opioid maintenance medicines for the treatment of dependence on opioid pain medicines |
| Opioid maintenance medicines for the treatment of dependence on opioid pain medicines |
| Opioid therapy for treating rheumatoid arthritis pain |
| Opioid treatment for opioid withdrawal in newborn infants |
| Opioids (chemical substance) for palliation for breathlessness in terminal illness |
| Opioids for abdominal pain in acute pancreatitis |
| Opioids for agitation in dementia |
| Opioids for cancer-related pain in children and adolescents |
| Opioids for chronic non-cancer pain in children and adolescents |
| Opioids for long-term treatment of noncancer pain |
| Opioids for managing pain in babies exposed to painful procedures |
| Opioids for neonates receiving mechanical ventilation |
| Opioids for neuropathic pain |
| Opioids for newborns receiving mechanical ventilation |
| Opioids for osteoarthritis |
| Opioids for the management of breakthrough pain in cancer patients |
| Opioids for the treatment of chronic low-back pain |
| Opioids for treating breathlessness at the end of life |
| Opioids for treating dyspnoea in patients with chronic heart failure |
| Opportunity for some keen tweeters to come to the Cochrane Colloquium 2018 |
| Optical aids for visually impaired children |
| Optical coherence tomography angiography for monitoring the treatment of neovascular age-related macular degeneration |
| Optical coherence tomography measurement of central retinal thickness to diagnose diabetic macular oedema |
| Optimal delivery management for the prevention of early neonatal SARS-CoV-2 infection |
| Optimal duration of chemotherapy for advanced non-small cell lung cancer |
| Optimal duration of exclusive breastfeeding |
| Optimal monitoring strategies for guiding when to switch first-line antiretroviral therapy regimens for treatment failure among adults and adolescents living with HIV in low-resource settings |
| Optimal timing for discontinuation of Pneumocystis jiroveci pneumonia prophylaxis in adult patients on highly active antiretroviral therapy (HAART) for HIV infection |
| Optimal timing for intravascular administration set replacement |
| Optimisation of chemotherapy and radiotherapy for Hodgkin lymphoma patients with respect to second cancers and survival |
| Optimization of fluid levels in people suffering hip fractures |
| Optimized anaesthesia depth guided by brain electrical activity for protection against postoperative delirium and cognitive dysfunction in adults |
| Optimum antibiotic doses for Helicobacter pylori eradication |
| Optimum force for tooth movement in orthodontic treatment |
| Optimum second-line regimens for eradication |
| Options for self-management education for adults with asthma |
| Oral 5-aminosalicylic acid compounds for maintaining remission in ulcerative colitis |
| Oral 5-aminosalicylic acid drugs for maintenance of medically-induced remission in Crohn's disease |
| Oral 5-aminosalicylic acid for maintenance of surgically-induced remission in Crohn’s disease |
| Oral 5-aminosalicylic acid for the treatment of active ulcerative colitis |
| Oral and intranasal aspirin desensitisation for non-steroidal anti-inflammatory drug (NSAID)-exacerbated respiratory disease |
| Oral and intrauterine progestogens for atypical endometrial hyperplasia |
| Oral and sublingual immunotherapy (giving people small amounts of things they are allergic to via their mouth or under their tongue) for fruit allergy |
| Oral anti-diabetic agents for women with diabetes or previous diabetes planning a pregnancy, or pregnant women with pre-existing diabetes |
| Oral antibiotics appear to be as effective as parenteral antibiotics in the treatment of severe pneumonia in children |
| Oral antibiotics for treating febrile neutropenia in cancer patients at low risk for complications |
| Oral antibiotics for treating infection with Pseudomonas aeruginosa in people with cystic fibrosis |
| Oral anticoagulants for preventing stroke in patients with non-valvular atrial fibrillation and no previous history of stroke or transient ischemic attacks |
| Oral anticoagulants for the secondary prevention of coronary heart disease |
| Oral anticoagulants versus antiplatelet therapy for preventing stroke and systemic embolic events in patients with atrial fibrillation |
| Oral anticoagulants versus antiplatelet therapy for preventing stroke in patients with non-valvular atrial fibrillation and no history of stroke or transient ischemic attacks |
| Oral anticoagulation plus an antiplatelet drug is better than anticoagulants alone for reducing death or blood clots after heart valve replacement |
| Oral antifungal drugs for treating athlete's foot (tinea pedis) |
| Oral antihistamine-decongestant-analgesic combinations for the common cold |
| Oral antihistamines for seasonal allergic conjunctivitis |
| Oral antiplatelet therapy for acute ischaemic stroke |
| Oral antivirals for preventing recurrence of herpes simplex virus keratitis |
| Oral antivirals for preventing recurrent herpes simplex keratitis in people with corneal grafts |
| Oral appliances and functional orthopaedic appliances for obstructive sleep apnoea in children |
| Oral appliances for obstructive sleep apnoea |
| Oral appliances for treating sleepiness, quality of life and markers of sleep disruption in people with obstructive sleep apnoea/hypopnoea (OSAH) |
| Oral aspirin for treatment of acute episodic tension-type headache in adults |
| Oral aspirin for venous leg ulcers |
| Oral baclofen for the management of spasticity in children with cerebral palsy |
| Oral beta-blockers for mild to moderate hypertension during pregnancy |
| Oral betamimetics for maintenance therapy after threatened preterm labour |
| Oral betamimetics for the prevention of preterm labour and birth for women with twin pregnancies |
| Oral budesonide for treatment of people with active ulcerative colitis |
| Oral Class I and III antiarrhythmic drugs for maintaining sinus rhythm after catheter ablation of atrial fibrillation |
| Oral contraceptives to treat cysts of the ovary |
| Oral corticosteroid treatment started by patients or parents during a severe asthma attack |
| Oral corticosteroids for bronchiectasis (stable and acute exacerbations) |
| Oral corticosteroids for induction of remission in ulcerative colitis |
| Oral corticosteroids for stable chronic obstructive pulmonary disease |
| Oral dextrose gel for prevention of low blood glucose levels in newborn babies |
| Oral dextrose gel for the treatment of newborn infants with low blood glucose levels |
| Oral etoposide for treatment and/or maintenance treatment of recurrent epithelial ovarian cancer |
| Oral evening primrose oil and borage oil for eczema |
| Oral fumaric acid esters for the treatment of psoriasis |
| Oral heath advice (education and training) for people with serious mental illness |
| Oral herbal therapies for treating osteoarthritis |
| Oral hormone therapies help reduce the frequency and severity of hot flushes and night sweats caused by menopause. |
| Oral hygiene care for critically ill patients to prevent ventilator-associated pneumonia |
| Oral hygiene programmes for people with intellectual disabilities |
| Oral ibuprofen for acute treatment of episodic tension-type headache in adults |
| Oral immunoglobulin for preventing necrotizing enterocolitis in preterm and low birth weight neonates |
| Oral immunoglobulin for the prevention of rotavirus infection in low birth weight infants |
| Oral immunoglobulin for the treatment of rotavirus diarrhea in low birth weight infants |
| Oral immunotherapy for the treatment of peanut allergy |
| Oral iron for people with chronic kidney disease |
| Oral Janus kinase inhibitors (tofacitinib) for maintenance of remission in ulcerative colitis |
| Oral janus kinase inhibitors for induction of remission in ulcerative colitis |
| Oral ketoprofen for treatment of acute episodic tension-type headache in adults |
| Oral killed cholera vaccines for preventing cholera |
| Oral killed cholera vaccines for preventing cholera |
| Oral magnesium supplementation for high blood pressure in adults |
| Oral medication for the treatment of women with gestational diabetes |
| Oral methylxanthines for bronchiectasis |
| Oral misoprostol for induction of labour |
| Oral morphine for cancer pain |
| Oral naltrexone as maintenance treatment to prevent relapse in opioid addicts who have undergone detoxification |
| Oral non steroid anti-inflammatories for children and adults with bronchiectasis |
| Oral non-steroidal anti-inflammatory drugs compared with other oral pain killers for sprains, strains and bruises |
| Oral nonsteroidal anti-inflammatory drugs (NSAIDs) for cancer pain in adults |
| Oral nonsteroidal anti-inflammatory drugs (NSAIDs) for neuropathic pain in adults |
| Oral NSAIDs for treating fibromyalgia pain in adults |
| Oral nutrition interventions in hospitalised older people at nutritional risk: a network meta-analysis of individual participant data |
| Oral nutritional supplements for treating venous leg ulcers |
| Oral or nasal steroids for otitis media with effusion (OME or 'glue ear') in children |
| Oral or topical nasal steroids for hearing loss associated with otitis media with effusion (glue ear) in children |
| Oral painkillers available without prescription for acute pain |
| Oral paliperidone for schizophrenia |
| Oral paracetamol for treatment of acute episodic tension-type headache in adults |
| Oral polio vaccine plus inactivated polio vaccine versus oral polio vaccine alone for reducing polio in children under two years of age |
| Oral potassium iodide for the treatment of sporotrichosis |
| Oral potassium supplementation for high blood pressure in adults |
| Oral probiotics for infantile colic |
| Oral probiotics for the treatment of infantile colic |
| Oral prostaglandin E2 for induction of labour |
| Oral protein-based nutritional supplement in people with chronic kidney disease requiring dialysis |
| Oral rehydration salt solutions for treating cholera: lower salt content versus higher salt content solutions |
| Oral retinoids for psoriasis |
| Oral rinses, mouthwashes and sprays for improving outcomes following tonsillectomy |
| Oral steroids for nasal polyps |
| Oral steroids for shoulder pain (adhesive capsulitis) |
| Oral steroids, splinting, ultrasound, yoga and wrist mobilisation provide short-term relief from carpal tunnel syndrome, but other non-surgical methods have not been shown to help. |
| Oral substitution treatment for injecting opioid users reduces drug-related behaviours with a high risk of HIV transmission, but has less effect on sex-related risk behaviours. |
| Oral sumatriptan for acute migraine |
| Oral tapentadol for cancer pain |
| Oral theophylline compared to placebo for people with chronic obstructive pulmonary disease (COPD) |
| Oral vaccines for preventing cholera |
| Oral versus inhaled antibiotics for people with bronchiectasis |
| Oral versus injectable ovulation induction agents for unexplained subfertility |
| Oral versus intravenous chemotherapy for colorectal cancer |
| Oral vitamin B12 compared with intramuscular vitamin B12 for vitamin B12 deficiency |
| Oral vitamin C supplements to prevent and treat acute upper respiratory tract infections |
| Oral water soluble contrast for cancer-related bowel obstruction |
| Oral xanthine derivatives (theophylline and doxofylline) for patients with stable chronic obstructive pulmonary disease (COPD) |
| Oral zinc for the prevention of hyperbilirubinaemia in neonates |
| Oral zinc supplementation for treating diarrhoea in children |
| Oral zinc supplements for treating leg ulcers |
| Oral vitamin A supplements to prevent acute upper respiratory tract infections in children up to seven years of age |
| Orbital therapy for adult thyroid eye disease |
| Organic nitrates for prevention of oesophageal varices bleeding and re-bleeding |
| Organisation of health services for preventing and treating pressure ulcers |
| Organisational and professional interventions to promote the uptake of evidence in emergency care: Effects on professional practice and health outcomes |
| Organisational interventions for decreasing the use of restrictive practices with children or adults who have an intellectual or developmental disability |
| Organisational interventions for improving control of blood pressure in individuals with hypertension |
| Organisational interventions for promoting person-centred care for people with dementia |
| Organisational level interventions for reducing occupational stress in healthcare workers |
| Organised inpatient (stroke unit) care |
| Organised trauma systems and designated trauma centres for improving outcomes in injured patients |
| Organising preventive care in community settings for people with heart disease |
| Organizational interventions for promoting person-centred care for people with dementia |
| Orientation and mobility training for people with low vision |
| Orlistat for the prevention of cardiovascular diseases in overweight or obese individuals |
| Orthodontic and orthopaedic treatment for anterior open bite in children |
| Orthodontic treatment for bimaxillary proclination in children and adults |
| Orthodontic treatment for deep bite and retroclined upper front teeth in children |
| Orthodontic treatment for prominent upper front teeth in children |
| Orthodontic treatment with appliances which move the upper molar teeth backwards |
| Orthodontics for treating temporomandibular joint (TMJ) disorders |
| Orthognathic surgery for surgical correction of patients with mandibular deficiency |
| Orthoses for mechanical neck disorders |
| Orthotic devices after stroke and other non-progressive brain lesions |
| Orthotic devices for the treatment of tennis elbow |
| Osmotic therapies added to antibiotics for acute bacterial meningitis |
| Osteotomy for treating knee osteoarthritis |
| Our evidence |
| Our funders and partners |
| Our global community |
| Our open access strategy |
| Our policies and positions |
| Our products and services |
| Outcome measures and needs assessment tools for schizophrenia and related disorders |
| Outcomes of patients who participate in randomized controlled trials compared to similar patients receiving similar interventions who do not participate |
| Outpatient interventions for smoking cessation and reduction for adults with a mental disorder |
| Outpatient psychological therapy for adults with anorexia |
| Outpatient treatment for cancer patient with low-risk febrile neutropaenic event is effective. |
| Ovarian ablation can improve longterm survival for pre-menopausal women with early breast cancer, but also has major adverse effects. |
| Ovarian cyst aspiration and IVF outcomes |
| Ovarian function suppression for treating premenopausal women with hormone receptor-positive early breast cancer |
| Ovarian suppression with LHRH agonists (such as goserelin) for treating premenopausal women with early breast cancer |
| Ovarian surgery for symptom relief in women with polycystic ovary syndrome |
| Over-the-counter (OTC) medications for acute cough in children and adults in community settings |
| Over-the-counter medications to help reduce cough for children and adults on antibiotics for acute pneumonia |
| Overall prognosis of acute and chronic musculoskeletal, widespread, and neuropathic pain in children and adolescents |
| Overdiagnosis due to screening mammography for women aged 40 years and over |
| Overground physical therapy gait training for chronic stroke patients with mobility deficits |
| Overview of all systematic review of all treatments for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) |
| Overview of Cochrane Reviews of interventions used during surgery for preventing surgical site infection |
| Overview of Cochrane's eight Review Group Networks |
| Overview of the safety of regular formoterol or salmeterol in adults with asthma |
| Overview of the safety of regular formoterol or salmeterol in children with asthma |
| Overview of ventilation strategies for the early management of intubated preterm infants |
| Ovulation induction with urinary follicle stimulating hormone versus human menopausal gonadotropin for clomiphene-resistant polycystic ovary syndrome |
| Ovulation suppression for endometriosis |
| Oxandrolone for growth hormone-treated girls aged up to 18 years with Turner syndrome |
| Oxatomide (antihistamine) for asthma in adults and children |
| Oxcarbazepine add-on for drug-resistant focal epilepsy |
| Oxcarbazepine add-on for drug-resistant partial epilepsy |
| Oxcarbazepine for acute affective episodes of bipolar disorder |
| Oxcarbazepine for neuropathic pain |
| Oxcarbazepine in the maintenance treatment of bipolar disorder |
| Oxcarbazepine versus carbamazepine monotherapy for partial onset seizures |
| Oxcarbazepine versus phenytoin monotherapy (single medication treatment) for epilepsy |
| Oxycodone for cancer-related pain in adults |
| Oxycodone for neuropathic pain in adults |
| Oxycodone for pain in fibromyalgia in adults |
| Oxygen breathing therapy for the relief of breathlessness in advanced terminal illness in adults |
| Oxygen therapy as part of the treatment for respiratory infections in children |
| Oxygen therapy during exercise training in chronic obstructive pulmonary disease (COPD) |
