Study	Reason for exclusion
Ahlstrom 1989	No placebo control.
Akural 2009	Medication administered preoperativley.
Anaokar 1993	No placebo control.
Apaydin 1994	No placebo control.
Apiou 1988	No placebo control.
Aranda 1989	No placebo control.
Averbuch 2000	Not an original report of trials, and unable to ensure that participants (total of 75 treated with ibuprofen) were not in another included study.
Bailey 1993	No placebo control.
Behotas 1992	Baseline pain intensity was not moderate to severe.
Bhounsule 1990	Did not state whether patients had a baseline pain of at least moderate intensity.
Biehl 1981	No placebo control.
Bloomfield 1974	Used 5 point pain intensity scale which is not validated for the data extraction method.
Calanchini 1991	No placebo control.
Carlos 1984	Could not be obtained despite attempts to contact the authors, ordering through the British Library and help from the librarians at Novartis and Knoll pharmaceuticals.
Carrillo 1990	Did not state when the interventions were administered but as the pain levels were recorded for the first 4 hours following surgery it may be assumed that they were given immediately postoperatively. Therefore insufficient baseline pain.
Chopra 2009	Medication administered at 1 hour, irrespective of baseline pain.
Cooper 1984	Inadequate description of method. Did not state whether interventions were randomly allocated or studies were double‐blind.
Cooper 1988b	Inadequate description of method. Did not state whether interventions were randomly allocated.
Cooper 1993	No placebo control.
Cooper 1996b	Intervention administered irrespective of postoperative baseline pain.
Darsow 1988	No direct pain outcome measured over the first 4‐6 hours (recorded motility etc in the days following surgery).
Dorfmann 1991	Inadequate description of method. Did not say whether the allocation was randomised, did not say when the interventions were administered postoperatively, no mention of the level of baseline pain and did not define the pain measurement used.
Doyle 2002	No usable data for ibuprofen treatment arm.
El‐Tanany 1993	No placebo control.
Fleiss 1979	Take medication "if experience pain". Cannot assume that all the patients included had a baseline pain of >moderate intensity.
Forbes 1991	Used a controlled release formulation of ibuprofen.
Frezza 1985	Could not be obtained despite attempts to contact the authors, ordering through the British Library and help from the librarians at Novartis and Knoll pharmaceuticals.
Gallardo 1980	Baseline pain intensity not moderate to severe.
Gallardo 1981	Data was only collected for three hours.
Garwood 1983	No placebo control.
Giles 1981	No placebo control.
Giles 1985	Did not state which scale was used.
Hazra 1982	Baseline pain intensity not moderate to severe.
Henderson 1994	No placebo control.
Henrikson 1982	Only presented the data for the placebo arm for the first hour.
Henrikson 1985	No placebo control.
Hopkinson 1980	Five point pain intensity scale and 5 point pain relief scale (including "worse") neither of which are validated for the data extraction method used. Global evaluation was the opinion of the investigators rather than the patient.
Hultin 1978	Cross‐over study with the first dose administered exactly 1 hour after the local anaesthetic rather than when the patient experienced at least moderate pain.
Hyrkas 1992	Intervention administered preoperatively. Therefore inadequate baseline pain.
Hyrkas 1993	Intervention administered preoperatively. Therefore inadequate baseline pain.
Hyrkas 1994	Intervention administered preoperatively. Therefore inadequate baseline pain.
Iles 1980	Data was only presented for one hour after administration of the interventions.
Iqbal 1986	Could not be obtained despite attempts to contact the authors, ordering through the British Library and help from the librarians at Novartis and Knoll pharmaceuticals.
Iwabuchi 1980	No placebo control.
Joubert 1977	Could not be obtained despite attempts to contact the authors, ordering through the British Library and help from the librarians at Novartis and Knoll pharmaceuticals.
Katharia 1992	Multiple dose study with no separate analysis of the first dose.
Khan 1992	No placebo control.
Kittala 1972	Intervention routinely administered to all participants irrespective of level of baseline pain.
Klein 1994	Abstract.
Mastronardi 1988	No placebo control.
Matthews 1984	First dose was administered immediately postoperatively irrespective of patients level of pain.
McEvoy 1996	No placebo control.
McQuay 1993	No placebo control.
Movilia 1990	First dose was administered immediately postoperatively irrespective of patients level of pain.
Nakanishi 1990	No placebo control.
Negm 1989	Included participants who took the medication when they were experiencing only mild pain.
Rondeau 1980	Baseline pain intensity not moderate to severe.
Rossi 1981	Inadequate description of method. Did not state whether study was double blind. Also data was only recorded for three hours.
Schleier 2007	No placebo control.
Shimura 1981	No placebo control.
Squires 1981	Intervention administered preoperatively. Therefore inadequate baseline pain.
Tai 1992	No placebo control.
Tani 1974	No placebo control.
Tesseroli 1986	The only measure of pain which was in the opinion of the patient rather than the investigator was the pain intensity VAS. At baseline, the mean VAS minus 1.96 x SD was less than 30 mm, therefore some patients included may have had a baseline pain intensity of less than moderate.
Troullos 1990	Intervention administered preoperatively. Therefore inadequate baseline pain.
Turcotte 1986	Baseline pain intensity not moderate to severe.
Van Der Zwan 1982	No direct pain outcome measurement used, pain assessed by analgesic intake.
Van Wering 1972	No placebo control.
Vigneron 1977	Could not be obtained despite attempts to contact the authors, ordering through the British Library and help from the librarians at Novartis and Knoll pharmaceuticals.
Vogel 1984	Combined the data from separate arms of a cross‐over trial into one data set.
Von Mayer 1980	Multiple dose study with no mention of the level of baseline pain.
Walker 1976	No placebo control.
Walton 1990	Intervention administered preoperatively. Therefore inadequate baseline pain.
Walton 1993	First dose was given im during surgery, then oral doses were given postoperatively at specified times rather than when patients had baseline pain of at least moderate intensity.
Weber 1990	No placebo control.
Winter 1978	Baseline pain intensity not moderate to severe.
Wuolijoki 1987	Interventions were administered either pre‐operatively or immediately post‐operatively. Therefore insufficient baseline pain.