Next: What Should be Done?
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The NHS's information management and technology (`IM&T') strategy has
caused many problems for patient privacy, which spurred the medical
profession into protest during 1995 and 1996. The strategy had been
justified in public on the grounds that it would enable a hospital
doctor treating a patient admitted unconscious to locate and access
the patient's medical records [6]. However, no such system
was built or even planned. Instead, the strategy revealed itself as
consisting of the following data collection systems.
- The NHS-wide Clearing service centralises all secondary care
payments, which used to be handled locally. It also provides
information to health authorities on referral patterns, readmission
rates and the like -- although similar services were already
available from commercial firms who work with de-identified data.
However, Clearing holds a fully identifiable record of each `contract
data set' which includes not just the patient's name, address,
diagnosis and treatment but also information such as HIV status, even
where this is irrelevant to the treatment. This was felt by the
medical profession to be an invasion of privacy [11]. In
addition, the costs of the Clearing service have become so high that
patient care has had to be cut to pay for them [5]. Also
objectionable is the main other function of Clearing -- to feed
information to:
- HES, the Hospital Episode Statistics database, contains
information on all secondary care episodes in the UK, and as noted
above it identifies patients by date of birth and postcode. According
to Caldicott, it is used for a wide range of central management
purposes, including trend monitoring, the support of ministers in
Parliament, and the provision of data for research and for health
sector businesses. This information is provided without the knowledge
or consent of the great majority of patients; it is thus clearly
unethical and in some cases illegal. However, in the view of the
Caldicott committee, the information flow is justified, and the
identifier -- the combination of postcode and date of birth -- must
be retained.
- The NHS number and the Tracing Service. The NHS is allocating
each actual or potential patient a number which can be looked up via
the tracing service (previously called the administrative
registers). There have been significant teething problems, with
millions of pounds wasted on systems that do not work [3].
If the NHS Executive can get it to work, the service will be the only
database to contain up-to-date information on the whereabouts of every
man, woman and child in the country. The access arrangements appear to
assume probity on the part of all those with legitimate access;
unfortunately this is unlikely to be the case. There will be a huge
incentive for large numbers of potential malefactors, ranging from
private detectives through organised criminals to foreign intelligence
agencies, to acquire access, whether by technical means or (more
likely) by corrupting staff; and the number of staff who have access
and are thus a target for corruption is in the hundreds of
thousands. The data that will thus be obtained will provide a history
of each patient's associations with healthcare providers, including
(for example) relationships with outpatient STD and psychiatric
clinics. Even if the security measures work (and we don't believe they
will) such data will still become widely visible throughout the NHS.
- Data collection from GPs. The standard GP contract includes a
capitation element plus additional payments for services such as
immunisation, screening, contraception, and minor surgery. The
processing of claims for these `items of service' has recently been
computerised, and this has made large quantities of personal health
information available to the centre. When the BMA objected, the
response of the NHS Executive's medical director was that these claims
did not contain personal health data [16] -- a curious view
given that the claim forms contain the names of women and girls
receiving contraceptive treatment!
There were also some unpredicted side-effects. For example, under-age
girls seeking contraception often give false names, and these passed
through the old manual system without problems. The new computerised
system rejects them: if the GP cannot supply an accurate name she does
not get paid.
- The Prescription Pricing Authority pays pharmacists, and has
recently acquired a role in the detection of fraud and drug abuse. It
supplies identifiable data to approved researchers (these are approved
by its medical director rather than by any process involving patient
consent), to the Drug Research Unit, and to the Fraud Unit. We
understand that it also gives the Home Office access to its database.
This led to objections from the BMA that it might be abused for
tracing illegal immigrants. (Health authorities already supply data on
migrants to the Office of National Statistics, according to
Caldicott.)
- Disease Registers. There are separate registers for a number of
expensive chronic diseases, particularly diabetes and HIV/AIDS
(information on which is collected by the Public Health Laboratory
Service at Colindale). HIV data is collected directly from GUM clinics
and from charities who receive funds for caring for victims; in both
cases, patients are identified by postcode and date of birth, and also
by the Soundex code of their surname. (The AIDS charities were not
even informed that this would enable their patients to be identified.)
In addition, results of CD4 tests are collected in fully identifiable
form. This is one of the cases where Caldicott suggests using less
personal information -- by replacing the patient's name with an
encrypted NHS number. The question of whether or not lab reports will
still be matched to other, identifiable, returns is ducked.
Further registers are planned for heart disease, stroke, etc., so the
development of diabetes registers and HIV data collection may be a
significant precedent. Although nominally designed to monitor the
quality of patient care, these registers have become entangled in
missions such as cost control. For example, there are growing
objections to some diabetes registers' use of identifiable patient
data. On the continent, data for such purposes are de-identified
before processing [10] so the intrusive and unethical aspects
of the current approach are clearly unnecessary.
- The NHS wide network is meant to connect all these systems
together. It is expensive (£1,500 per annum for an account, or
about 10 times market prices, and 1 p per kilobyte for normal traffic,
or about 100 times market price) and obsolete (being based on X.400
rather than on the SMTP protocol that has prevailed in the
marketplace). There are also safety and privacy problems: for example,
the previous government resisted pressure to protect the safety and
privacy of clinical messages using digital signature and encryption
mechanisms, and insisted that if these were used then copies of the
keys must be available to GCHQ. The recent change of government has
not ameliorated the pressure for government access to encryption keys,
despite the fact that a policeman armed with a warrant can always
obtain the plaintext directly from the GP's surgery and/or hospital.
These price and privacy problems led many hospitals and GPs to boycott
the network [4].
- Health authorities have computer systems that enable them to
collate all the expense claims submitted on behalf of a single
individual, whether for hospital care through Clearing, for drugs
through the PPA, or whatever. This procedure, known as `drill down',
creates a shadow patient record that is outside the control of the
patient and of the clinical professionals responsible for his
care. The predictable effect of `drill down' systems in the USA (where
they originated) has been to cause discrimination against patients
with expensive conditions [15] and to create intrusive
pressures on patients from employers and insurers for lifestyle
changes [12]. Local aggregation of data, such as drill-down,
appears to have been ignored by Caldicott.
The Caldicott list of data flows is not exhaustive, and new examples
surface regularly. Recently, the writer received a complaint from a
doctor injured in a road traffic accident. She received a letter from
the National Road Traffic Accident Claims Centre in Northampton,
asking for information about her accident, including whether she was
claiming personal injury compensation, and for information about the
lorry driver concerned. The director claimed to be acting for the
hospital under the Road Traffic Act 1988, and seemed to have received
this information from the hospital. The victim was outraged that the
hospital released her details to a third party, including her name and
address, the fact she required medical treatment and where the
treatment took place, without her informed consent. In this case,
hospitals appear to have been directed by the Department of Health to
outsource accident claims, without consultation and without due
consideration being given to the ethical aspects.
One can describe the essence of the privacy problem in terms of
aggregation of data. The likelihood that unauthorised use will be
made of information is a function of its value and the number of
people who have access to it; and building large databases increases
both of these risk factors simultaneously. Put simply, we can live
with the occasional disclosures that result from the record access
enjoyed by GPs' secretarial staff, but we would not accept a situation
in which the staff of all 36,000 GPs had access to the records of all
56,000,000 patients in the UK. Yet it is precisely this broad access
to huge datasets that is being deliberately engineered in many of the
systems being constructed in the NHS, and which the Caldicott
committee failed to identify and challenge.
Next: What Should be Done?
Up: Remarks on the Caldicott
Previous: Introduction
Ross Anderson
Thu Jun 25 15:00:54 BST 1998