Can you answer these five questions? The 15-minute home test that spots signs of Alzheimer's Questions range from writing date to working out change from shopping bill Others more vague such as 'how are corkscrew and hammer similar?' Test developed by US researchers to track condition of healthy older people Research: A study found the mini exam accurately identifies people with mild loss of mental function A 15-minute test you take at home can show up the first signs of mental decline nearly as well as diagnostic exams. The written test could be used to help catch and treat Alzheimer's early. US researchers who developed it say healthy older people would do the test at home and share the results with doctors so they could keep track of their condition. The questions range from simple feats of memory - writing the date, for example - to more complex everyday tasks, such as working out the amount of change needed when shopping. Other sections are more open-ended, with one asking: "How are a corkscrew and a hammer similar? Write down how they are alike. More than 1,000 people aged 50 and over were given the test, and the results indicated 28 per cent of them had cognitive impairment, a mild loss of mental function. That closely matched the results of detailed diagnostic tests on the same group, suggesting the test could be a useful indicator. Researcher Dr Douglas Scharre, director of cognitive neurology at Ohio State University, said that it could lead to dementia being diagnosed earlier. He said: "This self-administered test correlated very well with detailed cognitive testing. If we catch this cognitive change really early, then we can start potential treatments much earlier than without this test. While the test does not diagnose disease, it allows doctors to easily track changes in a patient's cognitive skills by observing how their answers change over time. Dr Scharre added: "We can give them the test periodically and, the moment we notice any changes in their cognitive abilities, we can intervene much more rapidly." Earlier research demonstrated that the test can detect four out of five people with mild thinking and memory issues. Around 95 per cent of people who do not have memory or thinking problems will get a normal score. Participants in the study were recruited from senior citizens" centres, health fairs, educational talks, and free memory screening advertised in newspapers. The test: US researchers say the home-test will be able to chart how healthy older people are progressing Doctors warn the test will not diagnose dementia, merely mild loss of mental function. It is still not known whether screening would be beneficial for Alzheimer's patients Volunteers were tested on mental orientation, language, reasoning, spatial ability, problem solving and memory. Dr Simon Ridley, from the charity Alzheimer's Research UK, warned that anyone concerned about memory loss should see a doctor. He said: "Further research is needed to confirm whether the test would be suitable to assess and track changes in people's memory and thinking skills. One drawback is that the test was not compared with existing cognitive tests. It's important to note that the test is not designed to diagnose dementia, and people who are worried about their memory should seek advice from a doctor rather than attempting self-diagnosis with a test at home. There is not enough evidence to suggest dementia screening for people who do not have memory concerns would be beneficial.