Contact tracing apps: a brief overview

A recent query forced me to update my understanding of contact tracing apps as used (or not!) during the current pandemic. I found resources such as these from The Register and the BCS helpful in gaining a rapid understanding. More recently, Claudia Pagliari has reviewed the ethics of contract tracing apps. Here's my brief summary:

Different countries have adopted different approaches to contact tracing. In some, GPS location tracking is used to establish when people were collocated. In others, QR code solutions, that record when people check in and out of buildings, can identify who was in the same building at the same time, but not whether they were ever in close physical proximity. Both these approaches may compromise people’s privacy as they depend on centrally storing data that identifies the phone, location, and time. Their technical effectiveness relies on the precision and accuracy of the data and the reliability of the matching algorithm that identifies collocated people.

A third approach, facilitated by Apple and Google, is decentralised. Put simply, this relies on Bluetooth connections between devices: devices exchange IDs (and potentially distance, inferred from signal strength). If the owner of one of the devices subsequently reports a positive test result then notification is sent to all phones for which the IDs have been stored within the past 14 days. This avoids recording location and is better for respecting individuals’ privacy; it also limits the utility of data for other purposes such as public health research.

The practical effectiveness of any solution depends on how many people adopt it (60% of the population is a widely used figure) and on people being collocated with their phones; some countries achieve this through regulatory means (e.g., by controlling people’s right to travel); others rely on “public spiritedness”.

All approaches rely on the accuracy and timeliness of reporting test results, and on the quality of app programming. Another potential limitation of contact tracing apps is that while different regions adopt different solutions, each only applies locally, and may be undermined by international travel.

In summary, there are many obstacles to implementing an effective contact tracing app that respects individual rights as enshrined in the laws of many countries. A well designed and deployed app may reduce infection rates but no app will eliminate Covid-19 without other, complementary, interventions.

Never mind the research, feel the governance

In the past 5 days, I have received and responded to:

• 16 emails from people in the university, the REC and the hospital about one NHS ethics application that required a two-word change to one information sheet after it had already been approved by both the university and the REC - but the hospital spotted a minor problem and now it has to go around the whole cycle again, which is likely to take several weeks at least.
• 6 emails about who exactly should sign one of the forms in a second ethics application (someone in the university or the hospital).
• 12 emails about the set of documents (I lost count of what's needed past 20 items) needed for a third application.

I dread to think what the invisible costs of all these communications and actions are, when scaled up to all the people involved in the process (and my part is a small one because I delegate most of the work to others), and to all the ethics applications that are going on in parallel.

I thought I was getting to grips with the ethics system for the NHS; I had even thought that it was getting simpler, clearer and more rational over time. But recent experiences show otherwise. This is partly because we're working with a wider range of hospitals than previously, and every one seems to have its own local procedures and requirements. Some people are wonderful and really helpful; others seem to consider it to be their job to find every possible weakness and block progress. I have wondered at times whether this is because we are not NHS employees (or indeed even trained clinicians). But it seems not: clinical colleagues report similar problems; in fact, they've put a cost on the delays that they have experienced through the ethical clearance process. Those costs run into hundreds of thousands of pounds. We don't do research to waste money like this, but to improve the quality and safety of patient care.

Today, there's an article in the Guardian about the under-resourcing of the health service and the impact this is having on patient care. Maybe I'm naive, but if the inefficiencies that we find in the process of gaining permission to conduct a research study in the NHS are replicated in all other aspects of health service delivery, it's no wonder they feel under-resourced.

Ethics and informed consent: is "informed" always best?

I am in the US, visiting some of the leading research groups studying human factors, patient safety and interactive technologies. This feels like "coming home": not in the sense that I feel more at home in the US than the UK (I don't), but in that these groups care about the same things that we do – namely, the design, deployment and use of interactive medical devices. Talking about this feels like a constant uphill struggle in the UK, where mundane devices such as infusion pumps are effectively "invisible".

One of the issues that has exercised me today is the question of whether it is always ethical to obtain informed consent from the patients who are receiving drugs via infusion devices. The group I'm working with here in Boston have IRB (Institutional Review Board, aka Ethics Board) clearance to just obtain informed consent from the lead nurse on the ward where they are studying the use of devices. Not even from all the nurses, never mind the patients. In one of our studies, we were only allowed to observe a nurse programming a device in the middle of the night if we had obtained permission to observe from the patient before they had fallen asleep (which could have been several hours earlier). Even though we were not gathering any patient data or disturbing the patient in any way. In fact, we were probably disturbing the patient more by obtaining informed consent from them than we would have been just observing the programming of the pump without their explicit knowledge.

We recently discussed the design of a planned study of possible errors with infusion devices with patient representatives. Feedback we got from one of them was: "patients and relatives need to have complete confidence in the staff and equipment, almost blind faith in many instances." There are times when ensuring that patients are fully informed is less important than giving them reassurance. The same is true for all of us when we have no control over the situation.

On the flight on the way here, there was an area of turbulence where we all had to fasten our seatbelts. That's fine. What was less fine what the announcement from the pilot that we shouldn't be unduly worried about this (the implication being that we should be a little bit worried): as a passenger in seat 27F, what use was it for me to worry? No idea! It made the flight less comfortable for me, to no obvious benefit (to me or anyone else).

Similarly with patients: if we accept that studying the use of medical devices has potential long-term benefits, we also need to review how we engage patients in the study. Does obtaining informed consent give them benefits or whatever-is-the-opposite? Maybe there are times where the principle of "blind faith" should dominate.

The ethics of ethics

Is ethics about doing good or about avoiding doing harm?

Last week, I was chatting with a Danish colleague, who is running user studies in several European countries as part of the MONARCA project. They are developing and testing novel technologies for the detection and management of bipolar disorder. Apparently, it took 15 months to obtain ethical clearance to conduct studies in one country. 15 months!

Processes were faster in other countries, but still measured in months rather than weeks. In the UK, our experience is that the time taken to get approval to conduct user studies, even of established technologies, is highly variable, and unpredictable. But always measured in months rather than days or weeks. So it is impossible to plan a research project in detail before ethical clearance and R&D approval have been obtained. But this is a high-effort process, so you don't want to embark on it until you're sure the study will be going ahead.

The challenge of getting ethical clearance can be a real disincentive to proposing research projects on healthcare technologies. Why embark on projects in healthcare when you can do equally interesting projects in other areas that don't put such barriers in the way?

There have been some very welcome improvements over the past couple of years, with more streamlined processes for audit studies and proportionate review. But the focus is still on avoiding harm regardless of potential benefits. “VIP” is a useful mnemonic for the main concerns:

• Vulnerability: particular care needs to be taken when recruiting participants from groups that might be regarded as vulnerable, such as children, the elderly, or people with a particular condition (illness, addiction, etc.)
• Informed consent: participants should be informed of the purpose of the study, and of their right to withdraw at any time.
• Privacy and confidentiality should be respected.

However, our work with clinicians and patients has really brought home to me that ethics goes beyond VIP. It should be about doing good, not just avoiding doing harm. But "doing good" might be in the long term: understanding current design and user experiences to guide the design of future technologies. And that doesn't directly address the need to engage positively with research participants. What motivates an individual clinician, patient or carer to engage with research on the design and use of medical technologies? There should be some positive benefit to participants.

For some, it will be about the "common good": about being prepared to invest time and expertise for long-term benefits. For others, there's an indirect pay-back in terms of having expertise and experience recognised and valued, or of being listened to, or having a chance to reflect on their condition, or their use of technology. There are probably many other complex motivations for participating in research. As researchers, we need to better understand those motivations, and respect them and work with them.

Why do clinician and patients engage in research on healthcare technologies? Because the perceive value – whether personal or societal – outweighs the perceived costs. Why do researchers engage in research on healthcare technologies? Ditto. The costs to all parties need to be proportionate to the benefits. So the ethics processes need to be proportionate, to encourage essential research. And as researchers we need to be mindful of the benefits, as well as the costs, to participants in research.