Scientometric impact assessment of a research policy instrument: the case of rating researchers on scientific outputs in South Africa

The influence of the National Research Foundation's (NRF) rating system on the productivity of the South African social science researchers is investigated scientometrically for the period from 1981 to 2006. Their output performance is mainly indicated by their research publications. Following international best practice in scientometrics as well as the behavioural reinforcement theory, we employed the "before/after control impact (BACI) method'', as well as the well known econometric breakpoint test as proposed by Chow. We use as control group the publications in the field of clinical medicine. The field is not supported by NRF and hence clinical medicine researchers are not affected by the evaluation and rating system. The findings show a positive impact of the NRF programme on the research outputs of social sciences researchers and the implementation of the programme has increased the relevant population of research articles by an average of 24.5% (during the first 5 years) over the expected number of publication without the programme. The results confirm the scientometric findings of other studies (e. g. that of Nederhof) that ratings promulgate research productivity.