Shipments of wearable devices, led by the healthcare and wellness market, totalled 14 million in 2011, according to a new report by IMS Research. Looking forward the report predicts the market will be worth at least US$6 billion in 2016 says the firm which it describes as “our most conservative forecast”.

Devices that wirelessly upload data such as vital signs or athletic performance currently include glucose or heart-rate monitors. In the future the market could expand to commonly include connected watches, glasses and sleep sensors.

Theo Ahadome, a senior analyst with the firm, said its 2016 forecast assumed the take-up of wearable technology would be limited by factors such as “a lack of suitable technology, poor user compliance and lack of an overall enhanced experience” compared with non-wearable products.

The firm’s more optimistic projections include the possibility of Google’s Smart Glasses or a rumoured Apple smart watch being successful as well as a further growth in the trend among consumers to seek more data about heath and fitness.