There are many screening and diagnostic tests available on the internet, as well as apps for mobile devices. But as with all things on the internet, not everything is an accurate source of information (see our Guide to online health advice).
Online health checkers
We've found some online tests from reputable sources which can provide a good starting point for any health concerns you have, or just for checking everything's OK. These are:
Body mass index (BMI)
Website: Better Health Victoria BMI calculator
Assesses: Weight in proportion to height.
You need: Your weight (kg) and height (cm).
BMI provides a guide to whether your weight is in the healthy range for your height, and is frequently used to assess risk for conditions such as heart disease. However, it has its limitations, and the body fat and waist-to-height ratio calculators below provide a better indication of health risk issues.
Website: Fitness calculators
Assesses: Approximate percentage of body fat relative to overall weight.
You need: Your waist, hip (women only) and neck circumference (cm), weight (kg) and height (cm).
Having too much or too little body fat can be bad for your health. BMI (above) is a starting point for identifying whether you’re overweight, but it doesn't distinguish between fat and muscle mass. This means people with a lot of muscle, such as athletes, may be heavier than someone of a similar size but with higher levels of fat, and fall in the "overweight" range. Other people, such as older people who tend to lose muscle tissue and gain fat as they age, may be in the "healthy" range, though they have high levels of body fat.
But measuring body fat accurately isn't easy, and isn't cheap either. This calculator is used by the US military and is considered accurate to within one to three per cent for most people. We tried it out on three staff members who also underwent bioelectrical impedance analysis, and found the results were very close.
Assesses: Waist circumference as a proportion of height.
You need: Your waist circumference (cm) and height (cm).
Beer bellies and love handles are a sign of excess abdominal fat. There are two main types of fat: subcutaneous, which is the layer of fat below the skin that feels soft and squishy; and visceral, which is fat found deeper in the abdomen, below the abdominal muscles and padding our abdominal organs (which is why some beer guts feel hard when prodded). Visceral fat is the more dangerous of the two because it affects metabolic and hormonal processes, and can increase the risk of diabetes and heart disease, as well as breast cancer for women.
Waist circumference is often used as a guide to increased risk of chronic diseases, but this little calculator takes your height into consideration for a slightly better risk estimate, especially for people who are a lot taller or shorter than average.
Many diseases are linked with excess abdominal fat, which can be indicated by your waist circumference. But where’s the waist? For those blessed with an hourglass figure it's pretty straightforward. Otherwise it's above the hip bone, approximately level with the navel. Another way to work it out is to bend sideways – the crease that's formed at the bend is where your waist is. Make sure the tape is level and firm against the skin, but not digging into it, and don't hold your breath.
Your disease risk
Website: Siteman Cancer Centre
Assesses: Risks of 12 different types of cancer, as well as bronchitis, emphysema, diabetes, heart disease, osteoporosis and stroke.
You need: Your weight and height, plus some knowledge of your immediate family health history.
Desirable: Cholesterol (total and HDL) in mg/dL (most countries, including Australia, use mmol per litre, but you can convert to mg/dL by dividing the number given in mmol/L by 0.0259).
Developed by the Harvard Center for Cancer Prevention, Your Disease Risk not only shows your risk of various lifestyle-related conditions relative to others of your age and gender, but also demonstrates key changes you can make to reduce risk, and pats you on the back for what you're doing right.
Assesses: Your risk of developing type-2 diabetes within the next five years.
You need: Waist circumference (in cm).
Caught in the early stages, the effects of type-2 diabetes on the cardiovascular system can be reduced or even prevented with appropriate management – diet, lifestyle and medication. However, many people aren't diagnosed until the disease has taken hold.
The AUSDRISK assessment tool, developed by the Baker IDI Heart and Diabetes Institute, can estimate your risk based on demographics, waist measurements and lifestyle. This tool accounts for different risks among ethnicities common in Australia, unlike tools based overseas (such as Your Disease Risk, above). If this risk assessment determines you're at a high risk of type-2 diabetes, it's recommended you see your doctor for follow-up tests – sooner rather than later.
Assesses: Approximate life expectancy.
You need: Your blood pressure, cholesterol (convert from mmol/L to mg/dL by dividing the number given in mmol/L by 0.0259) and waist and hip measurements to determine waist-to-hip ratio.
Are you blessed with genes for good health and longevity? Is your lifestyle helping or hindering your chances of getting that 100th birthday telegram from the Queen (or King, or President, as the case may be)? There are quite a few life expectancy calculators online – some more comprehensive than others – but any that take lifestyle into account rather than just simple demographics give fairly similar results. This one is nice because it’s all on one page and you can tweak the answers (improve your lifestyle!) and see instantly what difference it makes.
Depression and anxiety
Website: Beyond Blue
Assesses: Symptoms associated with various forms of anxiety and depression.
It's estimated that about 20% of adults are affected by some form of mental disorder every year, including anxiety disorders (which affect around 14% of the adult population each year) and depression (about 6%).
Beyond Blue is a joint State and Federal Government initiative working to address issues associated with depression, anxiety and related disorders in Australia. The Beyond Blue website provides checklists of symptoms for anxiety (including generalised anxiety disorder, panic disorder, post-traumatic stress disorder, obsessive compulsive disorder and phobias), depression, postnatal depression and bipolar disorder under the Symptoms Checklists tab. It's not a diagnostic tool, but it can help you determine whether or not you're experiencing a mental health disorder of any kind, and help you to determine the best ways to deal with it.
Website: The Right Mix
Assesses: Problem drinking.
Are you drinking too much? A recent survey of Australians found most people overestimated the number of drinks considered low-risk for short- and long-term harm, which could lead to risky drinking habits. This short Australian questionnaire can be used to identify problem drinking, so you can seek help if necessary. The website also has an interactive standard drinks guide, and other useful information about alcohol.