In Germany, studies in rehabilitation research--in particular evaluation studies and examinations of quality of outcome--have so far mostly been executed according to the uncontrolled one-group pre-post design. Assessment of outcome is usually made by comparing the pre- and post-treatment means of the outcome variables. The pre-post differences are checked, and in case of significance, the results are increasingly presented in form of effect sizes. For this reason, this contribution presents different effect size indices used for the one-group pre-post design--in spite of fundamental doubts which exist in relation to that design due to its limited internal validity. The numerator concerning all effect size indices of the one-group pre-post design is defined as difference between the pre- and post-treatment means, whereas there are different possibilities and recommendations with regard to the denominator and hence the standard deviation that serves as the basis for standardizing the difference of the means. Used above all are standardization oriented towards the standard deviation of the pre-treatment scores, standardization oriented towards the pooled standard deviation of the pre- and post-treatment scores, and standardization oriented towards the standard deviation of the pre-post differences. Two examples are given to demonstrate that the different modes of calculating effect size indices in the one-group pre-post design may lead to very different outcome patterns. Additionally, it is pointed out that effect sizes from the uncontrolled one-group pre-post design generally tend to be higher than effect sizes from studies conducted with control groups. Finally, the pros and cons of the different effect size indices are discussed and recommendations are given.

Back schools are educational programmes for the prevention and rehabilitation of back pain. A quantitative review (meta-analysis) was performed to synthesize the existing evidence on their effectiveness, for different outcome criteria and time categories. On the basis of a systematic literature research, 18 controlled back school studies with a total of 1682 participants could be included in the meta-analysis. Effect sizes that compared back school patients with patients in a control group were calculated for 14 outcome criteria and four time categories. Effectiveness of back schools was shown for the time period within 6 months of intervention. However, effects for the 14 examined criteria revealed large differences: in contrast to the strong effects on correct back posture and movements and on knowledge of back school contents, the intervention had only small effects on health economic variables (e.g. utilization of the health care system) and no effects on clinical variables (e.g. pain intensity). With regard to the time period following the 6 months after intervention, the analysed data does not strongly support the effectiveness of back schools. It is concluded that the effectiveness of back school intervention depends on the outcome criterion and time of measurement. The results suggest that the concept of back school programmes should be improved and systematically re-evaluated.

Up to now, the majority of rehabilitative measures in Germany has been performed in inpatient programmes. In the past 10 years an extension of outpatient rehabilitation can be noted. Because of new social welfare legislation the legal disadvantages for participants in outpatient rehabilitation have been eliminated on the 1st July 2001. In the past year, the Federal Rehabilitation Council as well as various rehabilitation providers have developed further and specified their concepts in outpatient rehabilitation. Concept requirements include still the principles of holism, interdisciplinarity, goal-oriented rehabilitation and team-work of rehabilitation staff. The extension of outpatient rehabilitation in the sphere of German pension insurance scheme is documented by the increase in models respectively regular services and rehabilitative measures. The results of the evaluation suggest, that the outpatient realisation of a comprehensive rehabilitation concept yields comparable results as the inpatient realisation. In some regions there is a strong cooperation between pension insurance institutes and corresponding health insurance companies in order to extend outpatient rehabilitation. A quality assurance program for outpatient rehabilitation will be developed. It can be expected, that the extension of outpatient rehabilitation goes on and that thereby the possibilities of a more flexible medical rehabilitation grow.

In 2002, the peer review for the somatic indications of medical rehabilitation was further developed. This process was aimed at adjusting the peer review checklist to the "Guide for the Uniform Medical Report of the Statutory German Pension Insurance Scheme" ("Leitfaden zum einheitlichen Entlassungsbericht der Rentenversicherung"), at harmonising the peer review with the version used in the quality assurance programme of the German health insurance and at reducing requirements by focusing on criteria relevant in the individual case. This paper reports on the consensus process carried out and outlines the modifications of the peer review procedure.

This paper reports the results of a peer review system that was implemented in the context of the quality assurance programme of the statutory German Pension Insurance scheme. The data reported refer to the 2000/2001 data collection period for medical rehabilitation in the somatic indications. Examination of inter-rater reliability for judgements of individual raters shows satisfactory results only in orthopaedics. In the quality assurance programme, rehabilitation centres are usually evaluated by the mean of 20 rater judgements. The reliability of this aggregated measure is satisfactory in all indications. The results of 561 rehabilitation centres show that those quality criteria are in particular need of improvement that refer to subjective concepts of patients (e. g., subjective theories of illness). Between peer review procedures in 1998 and 1999, the quality scores of rehabilitation centres had improved whereas between 1999 and 2000/2001, no further improvement can be shown. However, those rehabilitation centres with a low quality score in 1999 (lowest quartile of the distribution) underwent a positive development between 1999 and 2000/2001. Reasons for this trend and possibilities for improving interrater reliability of the peer review process as an element of the quality assurance programme of the German Pension Insurance scheme are discussed.