Aim: This study aimed to evaluate if the Timed Test for Money Counting (TTMC), complemented with testing the range of shoulder motion by gripping the back of the neck (NG), predicts the ability of geriatric inpatients to independently perform effective oral hygiene. Methods: This clinical study was conducted between May 2016 and May 2017 at the Geriatric Clinic of Jena University Hospital and involved 74 hospitalised geriatric inpatients aged between 66 and 98 years (mean age: 84.1 years). Oral examination included diagnosis of dental caries with the DMFT Index, periodontal health with the Periodontal Screening Index (PSI), dental plaque on natural teeth with the Turesky modified Quigley-Hein Index (TI), and plaque on removable dentures with the Denture Hygiene Index (DHI). Self- perceived oral hygiene was assessed by questionnaire. The TTMC and NG were performed and recorded, as were the completeness of the test procedure and the time needed to complete the test. After autonomous tooth brushing and denture cleaning by the patient, oral hygiene was scored again with the TI and DHI. Data regarding comprehensive geriatric assessment were collected from medical records. Ethics approval was obtained from the Ethics Committee of Jena University Hospital (4590-11/15). Results: Forty-nine (66.2%) geriatric inpatients completed the TTMC&NG successfully. Passing the TTMC&NG was significantly associated with better self-performed oral hygiene. There was a weak correlation between plaque reduction rates and the time needed to complete the test. The sensitivity of the TTMC&NG for above average plaque reduction was 86.4% on teeth and 77.8% on dentures. The test revealed a negative predictive value of 75.0% to detect below average plaque reduction on teeth and 72.7% for dentures. Conclusions: The TTMC&NG served as a suitable predictor for the ability of geriatric inpatients to autonomously perform effective tooth brushing and denture cleaning. The expenditure of time was only about 5 minutes and might help the medical staff to identify geriatric patients unable to perform effective oral hygiene independently. Keywords: oral Hygiene, timed test for Money counting, assessment