Table 2.

Functional classification of DHTs.

Evidence tier	Functional classification	Description	Includes (for example)	Excludes (for example)
Tier A: System impact DHTs with potential system benefits but no direct user benefits.	System service	Improves system efficiency. Unlikely to have direct and measurable individual patient outcomes.	Electronic prescribing systems that do not provide patient-level advice on prescribing. Electronic health record platforms. Ward management systems.	CE marked medical devices and systems that provide treatment or diagnoses, such as early warning systems that monitor patient vital signs.
Tier B: Understanding and communicating DHTs which help users to understand healthy living and illnesses but are unlikely to have measurable user outcomes.	Inform	Provides information and resources to patients or the public. Can include information on specific conditions or about healthy living.	DHTs describing a condition and its treatment. Apps providing advice for healthy lifestyles (such as recipes). Apps that signpost to other services.	Tools that collect symptom data from users. Tools that provide treatment for a condition. DHTs that allow communication among users, or between users and professionals.
	Health diaries	Allows users to record health parameters to create health diaries. This information is not shared with or sent to others.	Health tracking information such as from fitness wearables. Symptom or mood diaries.	DHTs that share information with professionals, carers or other users. Tools that provide treatment for a condition.
	Communicate	Allows 2-way communication between users and professionals, carers, third-party organisations or peers. Clinical advice is provided by a professional using the DHT, not by the DHT itself.	Instant messaging apps for health and social care. Video conference-style consultation software. Platforms for communication with carers or professionals.	DHTs that provide clinical content themselves (such as cognitive behavioural programmes for depression).
Tier C: Interventions DHTs for preventing, diagnosing and managing diseases. They may be used alongside other treatments and will likely have measurable user benefits. DHTs in the Treat, Active monitoring, Calculate or Diagnose categories will likely be CE-marked medical devices	Preventative behaviour change	Designed to improve health behaviours to prevent ill-health consequences associated with smoking, eating, alcohol use, sexual health, sleeping and exercise. Based on accepted behaviour change theories.	Smoking cessation DHTs and those used as part of weight loss programmes. DHTs marketed as aids to good sleep habits.	DHTs that describe themselves as a treatment for a diagnosed condition. Apps that provide general healthy lifestyle advice.
	Self-manage	Aims to help people with a diagnosed condition to manage their health. May include symptom tracking function that connects with a healthcare professional. May be based on accepted behaviour change theories.	DHTs that allow users to record, and optionally to send, data to a healthcare professional to improve management of their condition.	DHTs that describe themselves as a treatment for a diagnosed condition. Apps that automatically monitor and report data to a healthcare professional or third-party organisation.
	Treat	Provides treatment for a diagnosed condition (such as CBT for anxiety), or guides treatment decisions.	DHTs for treating mental health or other conditions. Clinician-facing apps that advise on treatments in certain situations. Electronic prescribing systems that provide patient-level advice on prescribing.	DHTs that provides general health advice or advice on living with a diagnosed condition. DHTs that offer general advice for clinicians such as online textbooks or digital versions of care pathways.
	Active monitoring	Automatically records information and transmits the data to a professional, carer or third-party organisation, without any input from the user, to inform clinical management decisions. Uses data to guide care or treatment.	DHTs linked to devices such as implants, sensors worn on the body, or sited in the home or care setting, where data are automatically transmitted for remote monitoring. Includes ward-based systems for monitoring and recording patient observations.	DHTs that allow a user to choose if and when to send recorded data to a professional, carer or third-party organisation.
	Calculate.	Tools that perform clinical calculations that are likely to affect clinical care decisions.	DHTs for use by clinicians, professionals or users to calculate parameters pertaining to care, such as early warning system software.	DHTs that diagnose or provide treatment for a condition.
	Diagnose.	Uses data to diagnose a condition in a patient, or to guide a diagnostic decision made by a healthcare professional.	DHTs that diagnose specified clinical conditions using clinical data.	DHTs that offer general lists of signs and symptoms for healthcare conditions.