Every move you make....Are you watching you?

Monitoring....There's something about getting something into numbers and targets that just makes it seem to be so controllable, isn't there? And many people - including many doctors - just love gadgets and measuring things. No wonder there is so much monitoring in health and fitness.

Actually, there's too much monitoring in some health matters. Some monitoring could cause anxiety without benefit, or lead to actions that do more harm than good.

Professor Paul Glasziou, author of Evidence-Based Monitoring, talked about this on Monday at Evidence Live. For monitoring to be effective there has to be:

• valid and accurate measurement,
• informed interpretation, and
• effective action that can be taken on the results.  

Then there has to be an effective monitoring regimen.

None of that is simple. Frequent testing can mean you end up acting on random variations, not real changes in health. There's more at Statistically Funny about when statistical significance can mislead and the statistical risks of multiple testing.

Self-monitoring can be a path to freedom and better health in some circumstances - if you use insulin or an anticoagulant like warfarin, for instance. But constant monitoring of everything you can measure is a whole other kettle of fish. You can read more about this, monitoring apps and 'the quantified self' in my guest blog at Scientific American: 'Every breath you take, Every move you make...' How much monitoring is too much?