• best evidence topic reports
• urinary tract infection
• deep vein thrombosis
• pulmonary embolism
• D dimer test
• paracetamol
• ketoacidosis

Best evidence topic reports (BETs) summarise the evidence pertaining to particular clinical questions. They are not systematic reviews, but rather contain the best (highest level) evidence that can be practically obtained by busy practising clinicians. The search strategies used to find the best evidence are reported in detail in order to allow clinicians to update searches whenever necessary. The BETs published below were first reported at the Critical Appraisal Journal Club at the Manchester Royal Infirmary¹ or placed on the BestBETs web site. Each BET has been constructed in the four stages that have been described elsewhere.² The BETs shown here together with those published previously and those currently under construction can be seen at http://www.bestbets.org.³ Five BETs are included in this issue of the journal together with another five that inform the accompanying accumulator BET.

• Accuracy of negative urine analysis in ruling out urinary tract infection in adults

• Venous blood gas in adult patients with diabetic ketoacidosis

• Antithrombotic treatment of below knee deep venous thrombosis

• Buccal nitrates in left ventricular failure

• Oral methionine compared with intravenous n-acetyl cysteine for paracetamol overdose

Accumlator BET

• Clinical probability scoring and pulmonary embolism

• Accuracy of combining clinical probability score and simpliRED d-dimer for diagnosis of pulmonary embolism

• IL d-dimer test in the diagnosis of pulmonary embolism

• Outpatient investigation of pulmonary embolism

• Outpatient treatment of pulmonary embolism