Background An internal pilot study is the first part of a substantive RCT where trial parameters are examined and data contribute to the final analyses. This two-phase design provides an opportunity to review pre-agreed ‘progression criteria’ that determine whether the internal pilot should continue into the main trial. Selecting appropriate criteria is critical but little is known about this a...

If a configuration of m triangles in the plane has only n points as vertices, then there must be a set of max { dm/(2n− 5)e Ω(m3/(n6 log n)) triangles having a common intersection. As a consequence the number of halving planes for a three-dimensional point set is O(n log n). For all m and n there exist configurations of triangles in which the largest common intersection involves max {dm/(2n− 5)...

THE marriage relationships of two groups of 100 service men and their wives, normally resident in Greater London, are reviewed. All the men were hospital patients between 1943 and 1946. One group were admitted for neurotic illness (neurotic group) and the other for illness or injury without neurosis (control group). Data were collected by personal interview only from married couples who were wi...

Traumatic dislocation of the knee is an uncommon but serious injury, associated with extensive soft-tissue damage and the danger ofneurological and vascular involvement. Kennedy (1963) described twenty-two cases, discussing the mechanism of production and the high incidence of popliteal artery involvement, particularly in anterior dislocations. Griswold ( 195 1 ) and Quinlan and Sharrard ( 1958...