DIY diagnostics – to do or not to do

Much like do-it-yourself (DIY) hardware stores, DIY or at-home diagnostic test kits possess both benefits and drawbacks. Making a decision is tricky. It may become even more so as a host of new kits arrive on the market, some of which are aimed at potentially deadly diseases like cancers.

The growth in the DIY kit market is driven by a combination of several factors:

• Access to new technologies, such as DNA sequencing databanks which can pinpoint a range of diseases, or nanowires coupled to biomarker sensors and/or protein-specific monoclonal antibodies.

• The increasing cost of healthcare, especially in the US. DIY cholesterol tests, for example, cost 30-40 USD, or one-fifth the level charged by a physician.

• Longer waiting times for lab tests, both in the US and some parts of Europe.

Many kit developers are beginning to see easier opportunities in the developing world, especially in large emerging countries such as Brazil, India and China. All these have a rising number of affluent consumers, accompanied by lifestyle changes which heighten the risk of diseases such as diabetes or AIDS. At the same time, medical regulations are more lax than in the West; for example, it is not impossible that kits are packaged differently, without the visible labels which warn that a specific test is not (yet) approved by health regulators.

What is common to both the West and large emerging markets, as far as DIY test kits go, is the Internet. Not only does the Net allow consumers to become aware of new tests, but it also provides them a channel for access to vendors, credit card payments and delivery by mail order. As a follow-on, some DIY kit producers are working to provide encrypted transfer of data and access to the test results, again over the Internet.

No one doubts the utility of DIY kits in areas such as ovulation and pregnancy testing. Most physicians also agree that the monitoring of chronic diseases is far better served by emerging DIY diagnostic technologies. For example, a relatively new test for patients taking the anticoagulant warfarin does away with the need for weekly visits to a physician – to ensure that their blood is neither too thick to cause a stroke, nor too thin to be life threatening in case of a wound or high blood pressure. This is also the case for at-home diabetes tests, which permit day-to-day modifications in insulin intake. Blood pressure too, it is now accepted, needs to be monitored throughout the day to give a true reading, rather than once at a doctor’s.

However, there are several areas where healthcare professionals are apprehensive about the growth in DIY tests, and are likely to remain so for some time. This is mainly because even state-of-the-art DIY technology has an approximately 10% risk of error. While the psychological impact of a false positive – which has a similar error level to false negatives in most DIY tests – can be serious, a false negative on a major allergy, urinary tract or yeast infection, or for that matter, HIV, would be devastating.