Characteristics and publication output from 191 drug trials initiated between 1998 and 2007 involving Norwegian general practice trial sites*
| Total (%) | Journal publication | No journal publication | p Value† | ||
|---|---|---|---|---|---|
| Results posted elsewhere‡ | No results posted | ||||
| All trials | 191 (100) | 135 (71) | 22 (12) | 34 (18) | |
| Active comparator | 0.040 | ||||
| Yes | 117 (100) | 89 (76) | 12 (10) | 16 (14) | |
| No | 74 (100) | 46 (62) | 10 (14) | 18 (24) | |
| Trial setting | 0.79 | ||||
| General practice only | 42 (100) | 29 (69) | 6 (14) | 7 (17) | |
| Mixed setting | 149 (100) | 106 (71) | 16 (11) | 27 (18) | |
| International trial | 0.59 | ||||
| Multinational | 177 (100) | 126 (71) | 21 (12) | 30 (17) | |
| National | 14 (100) | 9 (64) | 1 (7) | 4 (29) | |
| Trial duration (weeks) | 0.025 | ||||
| Median | 24 | 12 | 16 | ||
| (min–max) | (2–288) | (2–240) | (1–96) | ||
| Sample size (n patients) | 0.010 | ||||
| Total | 334 255 (100) | 269 526 (81) | 23 321 (7) | 41 408 (12) | |
| Median | 760 | 564 | 550 | ||
| (min–max) | (8–31 000) | (80–4830) | (50–14 317) | ||
| Norway (median) | 70 | 50 | 50 | ||
| Trial investigators (Norway only) | |||||
| Median | 7 | 8 | 7 | ||
| (min–max) | (1–402) | (3–16) | (1–31) | ||
| Trial phase (n=119 due to missing data) | |||||
| Phase II | 14 (100) | 6 (43) | 5 (36) | 3 (21) | |
| Phase III | 74 (100) | 56 (76) | 6 (8) | 12 (16) | |
| Phase IV | 31 (100) | 24 (77) | 1 (3) | 6 (19) | |
| Drug (ATC group§) | |||||
| Diabetes drugs (A10) | 40 (100) | 26 (65) | 3 (8) | 11 (28) | |
| Obstructive airways drugs (R03) | 24 (100) | 19 (79) | 2 (8) | 3 (13) | |
| Renin-angiotensin drugs (C09) | 20 (100) | 18 (90) | 1 (5) | 1 (5) | |
| Lipid modifying drugs (C10) | 17 (100) | 12 (71) | 1 (6) | 4 (24) | |
| Anti-inflammatory drugs (M01) | 11 (100) | 9 (82) | 0 (0) | 2 (18) | |
| Other ATC groups | 79 (100) | 51 (65) | 15 (19) | 13 (16) | |
| Sponsor of trial | |||||
| GlaxoSmithKline | 38 (100) | 23 (61) | 7 (18) | 8 (21) | |
| AstraZeneca | 32 (100) | 26 (81) | 4 (13) | 2 (6) | |
| Novartis | 20 (100) | 17 (85) | 1 (5) | 2 (10) | |
| MSD | 19 (100) | 15 (79) | 1 (5) | 3 (16) | |
| Pfizer | 11 (100) | 7 (64) | 0 (0) | 4 (36) | |
| Non-industry | 7 (100) | 5 (71) | 0 (0) | 2 (29) | |
| Other drug companies (n=25) | 64 (100) | 42 (66) | 9 (14) | 13 (20) | |
*Five trials were planned but not started, and are therefore not included in the table.
†χ2 test for differences between journal publication and no journal publication. For trial duration and sample size, the categories of ≥or <median were used.
‡Trial results reported at clinicaltrials.gov, sponsors' trial registry or as an abstract were defined as results reported elsewhere.
§ATC: Anatomical Therapeutic Chemical classification system, the drug classification system used by WHO.19
Bold typeface indicates p<0.05.