Table 1.
 Characteristics of randomised placebo controlled trials included in review of efficacy and safety of paracetamol for spinal pain and osteoarthritis
| Study | Details of participants | Interventions (Dose regimens) | Outcomes and time points |
|---|---|---|---|
| Spinal pain | |||
| Nadler, 200245 | 133 patients (group 1=113, group 2=20); mean age (SD) group 1=34.9 (11.3), group 2=38.0 (9.1); duration: acute (NR) | Group 1: paracetamol 500 mg, 2 tablets, 4 times daily, 4000 mg total. Group 2: oral placebo | Pain (VRS, 0-5); Roland Morris questionnaire (0-24); adverse events; on days 2 and 4 |
| Wetzel, 201452 (cross over) | 40 patients on chronic opioid therapy, mean age (SD)=57.2 (12.8); duration: chronic (>6 months) | Group 1: single intravenous paracetamol 1000 mg dose. Group 2: intravenous placebo | Pain (VAS, 0-10); Roland Morris questionnaire (0-24); immediately after infusion |
| Williams, 201453 | 1652 patients (group 1=550, group 2=549, group 3=553); mean age (SD) group 1=44.1 (14.8), group 2=45.4 (16.7), group 3=45.4 (16.7); duration: acute (<6 weeks) | Group 1: paracetamol 665 mg, 2 tablets, 3 times daily, 3990 mg total. Group 2: paracetamol 500 mg 1-2 tablets as required, 4-6 hours apart, maximum 8 tablets per day. Group 3: oral placebo. Rescue medication allowed | Pain (NRS, 0-10); Roland Morris questionnaire (0-24); SF-12 physical score (0-100); patient adherence; rescue medication; adverse events; at 1, 2, 4, and 12 weeks |
| Osteoarthritis | |||
| Amadio, 198343 (cross over) | 25 patients; median age (range)=64 (43-80); duration: NR | Group 1: paracetamol 500 mg, 2 tablets, 4 times daily, 4000 mg total. Group 2: oral placebo | 50 ft (15 m) walking test; adverse events; at 4 weeks |
| Zoppi, 199544 | 60 patients (group 1=30, group 2=30); mean age (SD) group 1=57.6 (11.2), group 2=55.3 (11.9); duration: group 1=75.0 (98.2) months, group 2=45.8 (58.6) months | Group 1: effervescent paracetamol 500 mg, 2 tablets, 3 times daily, 3000 mg total. Group 2: effervescent placebo | Pain (VAS, 0-100); adverse events; at 1 week |
| Case, 200346 | 57 patients (group 1=29, group 2=28); mean age (SD) group 1=62.1 (11.4), group 2=61.7 (9.0); duration: NR | Group 1: paracetamol 500 mg, 2 tablets, 4 times daily, 4000 mg total. Group 2: Oral placebo | WOMAC pain (VAS, 0-500); WOMAC function (0-1700); adverse events; at 2 and 12 weeks |
| Golden, 200447 | 303 patients (group 1=148, group 2=155); mean age (SD) group 1=61.1 (13.1), group 2=60.3 (13.0); duration: NR | Group 1: paracetamol 1000 mg, 1 tablet, 4 times daily, 4000 mg total. Group 2: Oral placebo | Pain intensity on weight bearing (0-4); 50 ft (15 m) walking test; adverse events; at 1 week |
| Miceli-Richard, 200448 | 779 patients (group 1=405, group 2=374); mean age (SD)=70 (11); duration: 46 (47) months | Group 1: paracetamol 1000 mg, 1 tablet, 4 times daily, 4000 mg total. Group 2: oral placebo. Rescue medication not allowed | Pain (VAS, 0-100); WOMAC function (0-100); adverse events; patient adherence; at 1 and 6 weeks |
| Pincus, 2004a (PACES-A cross over trial)49 | 524 patients; mean age (SE) group 1=63.7 (1.2), group 2=62.8 (1.3); duration group 1: 8.5 (1.0) years, group 2: 8.1 (1.1) years | Group 1: Paracetamol 1000 mg, 1 tablet, 4 times daily, 4000 mg total. Group 2: Oral placebo. Rescue medication allowed | MDHAQ pain (VAS, 0-100); WOMAC (0-100); adverse events; at 6 weeks |
| Pincus, 2004b (PACES-B cross over trial)49 | 556 patients; mean age (SE) group 1=64.8 (1.3), group 2=63.4 (1.3); duration group 1: 10.4 (1.3) years, group 2: 9.5 (1.1) years | Group 1: paracetamol 1000 mg, 1 tablet, 4 times daily, 4000 mg total. Group 2: oral placebo. Rescue medication allowed | MDHAQ pain (VAS, 0-100); WOMAC (0-100); adverse events; at 6 weeks |
| Herrero-Beaumont, 200751 | 212 patients (group 1=108, group 2=104); mean age (SD) group 1=63.8 (7.2), group 2=64.5 (6.9); duration: group 1: 6.5 (5.3) years, group 2: 7.2 (5.8) years | Group 1: paracetamol 1000 mg, 1 tablet, 3 times daily, 3000 mg total. Group 2: oral placebo. Rescue medication allowed | WOMAC pain (Likert, 0-20); WOMAC function (0-68); rescue medication; adverse events; at 6 months |
| Altman, 200750 | 483 patients (group 1=160, group 2=158, group 3=165); mean age (range)=62.2 (40-90); duration: NR | Group 1: paracetamol ER 1300 mg, 3 times daily, 3900 mg total. Group 2: paracetamol 650 mg, 3 times daily, 1950 mg total. Group 3: oral placebo. Rescue medication allowed | WOMAC pain (VAS, 0-100); WOMAC function (0-100); adverse events; at 12 weeks |
| Prior, 201454 | 542 patients (group 1=267, group 2=275); mean age (SD) group 1=61.7 (10.2), group 2=61.7 (10.1); duration: NR | Group 1: paracetamol ER 650 mg, 2 tablets, 3 times daily, 3900 mg total. Group 2: oral placebo. Rescue medication allowed, but limited | WOMAC pain (VAS, 0-100); WOMAC function (0-100); adverse events; at 2 and 12 weeks |
VRS=verbal rating scale, VAS=visual analogue scale, NRS=numeric rating scale, NR=not reported, WOMAC=Western Ontario and McMaster Universities arthritis index, MDHAQ=multi-dimensional health assessment questionnaire, SF-12=12-item short form health survey, Duration=duration of condition, ER=extended release.