The aim of the present study was to determine the nature of the knowledge and skills related to professional expertise, and to develop means by which such expertise may be individually measured. An instrument was developed consisting of ® ve different scales (with contents ranging from 12 to 19 items each), each re¯ecting one of ® ve dimensions: knowledge, meta-cognitive knowledge, skills, social recognition, growth and ¯exibility. Participants were two different, but relevant, groups of raters: individual employees (N 5 558) and their immediate supervisors (N 5 454). The item-sets for both groups are nominally identical, except that the wording was adapted when necessary to suit one group or the other. The reliabilities of the developed scales were high with Cronbach's a ranging from 0.83 to 0.94, for both the self-ratings and the supervisor ratings. All ® ve scales are homogeneous and distinctive as corroborated by Multitrait-Multimethod and LISREL analyses. Background and construction of the instrument are discussed at length and the instrument is appended in two versions: the original Dutch questionnaire and an English version.

Although role stress literature has almost exclusively focused on individual role incumbents, it is conceivable that shared conditions of ambiguity, conflict, and quantitative or qualitative overload may give rise to a collective experience of role stress in teams. Testing a multilevel mediation model among 38 Dutch project teams ( N = 283), we studied the interplay among individual and team role stress, team learning behaviors, and individual and team performance. Team role stress was discerned as a separate construct next to individual role stress. Team quantitative role overload, in particular, impeded team and individual performance by inhibiting team learning behaviors and, indirectly, also hindered individual performance by increasing individual quantitative overload.

Troost, J., Staal, G. E. /., Willemse, J. and van der Heijden, M. C. M.: Fucosidosis. I. Clinical and enzymological studies. Neuropadiatrie 8: 155-162 (1977). Three new cases of fucosidosis are described. The symptomatology of two patients started in the first year of life. Firstly a delay of psychomotor development was noted. Then hypotonia developed. Both children, brother and sister, suffered from frequent respiratory infections. The hypotonia of the eldest patient changed gradually into severe spasticity and ultimately into decerebrate rigidity. Both patients had coarse facial features, resembling those of the mucopolysaccharidoses. Hepatomegaly existed in both children. Angiokeratoma corporis diffusum did not occur in this pedigree. Radiological examination of the skull revealed severe sclerosis and hyperostosis of the base of the skull. X-rays of the vertebral column revealed the same abnormalities of the vertebrae as seen in the mucopolysaccharidoses. Electronmicroscopy of N. suralis and liver biopsy showed storage material, some of which had a very regular lamellar structure. The activity of a-L-fucosidase in the leucocyte was deficient. The enzyme activity of the parents was in the heterozygote range. The clinical expression of the third patient was totally different. The age of onset was 7 2 /i2 years. The disease started with focal neurological symptoms: left sided myoclonus and a left sided hemiparesis. In the course of a year a gradual regression of mental capacities and motor skills became evident. There were no features resembling to mucopolysaccharidoses, nor radiological abnormalities. Enzymological investigations showed deficiency of the activities of a-L-fucosidase and arylsulfatase A. The reduction of the a-L-fucosidase was however less than in the "classical" cases. It is suggested, that the combined reduction of both enzyme activities is a condition for the clinical expression of the disease and for its late onset as well. Fucosidosis