PROBLEM: There is a strong relation between mobility, walking safety and living independently in old age. People with walking problems suffer from fear of falling and tend to restrict their mobility and performance level in the community environment--even before falls occur. This study was planned to test the validity and prognostic value of a fall risk screening instrument ("Sturz-Risiko-Check") that has already shown its feasibility, acceptance and reliability, targeting independently living senior citizens. METHODS: The study sample was recruited from a sheltered housing complex in Hamburg (with written consent). Persons with need of professional care ("Pflegestufe" in Germany) were excluded. The residents were asked to fill in the multidimensional questionnaire ("Sturz-Risiko- Check"). In a second step, a trained nurse asked the participants in a phone call about their competence in the instrumental activities of daily living (I-ADL mod. from Lawton, Brody 1969) and about their usual mobility performance level (e.g. frequency and distance of daily walks, use of public transport). According to the number and weight of self-reported risk factors for falling, three groups: "low fall risk", "medium fall risk" and "high fall risk" were classified. Finally, this classification was re-tested after one year, asking for falls and fall related injuries. RESULTS: A total of 112 senior citizens without need of personal care, living in a sheltered housing facility were asked to participate. Acceptance was high (76.1%). Self-reported data from 79 participants concerning falls, fall-risk, mobility and instrumental activities of daily living were included in the statistical analyses. Mean age was 78 (64 to 93) years and associated by a high percentage of women (75.9%) in this sample. The older participants reported 0 to 13 different factors (mean 5) related to a high risk of future falls. Most participants (78.5%) quit cycling because of fear of falling. There was a high incidence in the study sample and over the three risk groups of chronic disorders like cardiac failure (75.9%) and disturbed vision or hearing (64.6%). According to the rising risk of falling over the three risk groups (low, medium and high), there were symptoms of fast functional decline or frailty like diminished walking speed (6.3 vs 36.8 vs 72.0%), sarcopenia (failed chairrise test: 0 vs 18.4 vs 28%) or already perceived fall events (0 vs 5.3 vs 56.0%) and ongoing restriction in basic activities. Those results were proven by the data on fall frequencies after one year (follow-up). We found an increase in falls over all three risk groups (12.5 vs 31.6 vs 28%) with fall-related severe injuries (fractures) in two persons classified in the high fall-risk group. DISCUSSION: The results of the fall-risk screening were useful to classify groups with different probability to fall in the near future. Fear-offalling and symptoms of frailty were related to an increasing risk of falling and loss of mobility and autonomy in still independently living senior citizens. CONCLUSION: The fall-risk screening instrument ("Sturz-Risiko-Check" questionnaire) was useful and valid to predict risk of falling and functional decline in independently living senior citizens transitioning to frailty. This screening will be part of a prevention approach in the City of Hamburg to offer primary and secondary prevention interventions adapted to special target groups of community- dwelling elder people (robust in contrast to frail elderly). The implementation should be accompanied by training sessions for physicians in the primary care sector and health improvement programmes for elder citizens.