Research graph
References from Pragmatic controlled clinical trials in primary care: the struggle between external and internal validity. Local targets link to admitted publications; unresolved targets remain external evidence.
10.1136/bmj.311.7017.1382
10.1136/bmj.311.7017.1382 · 1995 · External reference
10.1034/j.1399-3038.2002.00194.x
10.1034/j.1399-3038.2002.00194.x · 2002 · External reference
10.1192/bjp.175.3.217
10.1192/bjp.175.3.217 · 1999 · External reference
10.1136/bmj.316.7127.285
10.1136/bmj.316.7127.285 · 1998 · External reference
10.1002/1097-0258(20010215)20:3<331::aid-sim795>3.0.co;2-k
10.1002/1097-0258(20010215)20:3<331::aid-sim795>3.0.co;2-k · 2001 · External reference
Unresolved reference
2000 · External reference
10.1016/0021-9681(67)90041-0
10.1016/0021-9681(67)90041-0 · 1967 · External reference
10.1017/s0266462300007406
10.1017/s0266462300007406 · 1989 · External reference
