WORLD PSYCHIATRIC ASSOCIATION
Position Statement on the Use and Safety of Electroconvulsive Therapy
Prepared on behalf of the WPA Section on Biological Psychiatry by:
Mohammed T Abou-Saleh,
Chair of the WPA Section on Biological Psychiatry
St George’s Hospital Medical School
Cranmer Terrace
London SW17 ORE , UK
Tel 00442087252802
Fax 00442087252914
Email:mabousal@sghms.ac.uk
Yiannis Papakostas
yiargeke@hol.gr
Ioannis Zervas
Zervas@compulink.gr
George Christodoulou
gnchrist@compulink.gr
Secretary for Sections, World Psychiatric Association
President, International College of Psychosomatic Medicine
Papadiamantopoulou 11 str., 115 28 Athens, GREECE
Tel.: +30 210 72 91 389
Fax: +30 210 72 42 032
E-mail: gnchrist@compulink.gr
This position statement on the use and safety of electroconvulsive therapy (ECT) has been prepared on
behalf of the WPA Section on Biological Psychiatry at the request of the Executive Committee of the
WPA. The statement is informed by available evidence and reference will be made to guidelines produced
by a number of authoritative bodies, including the American Psychiatric Association, the Royal College
of Psychiatrists, the UK National Institute of Clinical Excellence (NICE) and the World Federation of
Societies of Biological Psychiatry. Moreover, for depressive disorders particular reference will be made to
the recently published systematic review and meta-analysis by the UK ECT Review Group (2003) .
Introduction
Electroconvulsive therapy (ECT) is an important though controversial treatment for
certain subgroups of individuals suffering from severe mental disorder. These subgroups
consist primarily of patients with severe depressive disorder, catatonia, mania and
occasionally certain patients with schizophrenia. In addition, depending on the comorbidity with medical and / or neurological disorders and on the risk analysis in relation
to the necessity to treat, ECT can be administered either as a low risk or a high risk
procedure. ECT should be administered following valid and informed consent by the
patient when appropriate and in adherence to a set of guidelines of administration
procedures.
The scope of this statement is to consider the evidence for the efficacy of ECT in the
treatment of depressive and other psychiatric disorders and its safety and determine its
optimum use with continuation pharmacotherapy and provide recommendations for
practice.
Depressive Disorders
The introduction of ECT for the treatment of severe depressive illness is one of the most
dramatic developments in psychiatry. It is widely considered to be the most effective
treatment for severe depressive illness compared with all other modalities including the
range of pharmacological treatments. Since its introduction in the early 1930s it has
undergone important development and improvement with the use of anaesthesia and
muscle relaxation which rendered it more safe and acceptable. The recall of ECT in the
US in the 1970s was “plagued by hostility to the treatment” (Fink, 2001) fuelled by
images of barbaric, inhumane and coercive treatment. In contrast to such an approach,
many national psychiatric associations and societies have promoted ECT and many
countries have introduced guidelines for practice: Australia, Canada, New Zealand, UK
and the US ( Bauer et al,2002). It is however of considerable concern that in many third
world countries, ECT is still used without the benefit and safety of anaesthesia or
modern ECT devices (Fink, 2001).
Full review of the successful management of depressive disorders is beyond the scope of
this Position Statement. It should however be based on comprehensive assessment,
formulation and implementation of a treatment plan. Treatment is categorised into an
acute phase to induce a remission in the disorder over a period of 6 to 8 weeks, a
continuation phase to maintain remission and to achieve recovery over a period of 16 to
20 weeks to prevent a relapse in the disorder and a prophylatic/maintenance phase to
prevent a recurrence in the disorder (occurrence of a new episode of illness) the duration
of which is dependent upon the previous frequency and severity of the disorder.
Assessment
Comprehensive assessment of the patient includes the following components: Diagnostic
evaluation to determine the diagnosis of the episode of illness and whether the patient is
suffering from bipolar depression or non bipolar depression with or without melancholia
or psychotic features including delusional depression. Evaluation of the safety of the
patient and others based on assessment of risk of self harm or harm to others.
Evaluation of risk is based on presence of suicidal or homicidal ideas intent and plans;
access to means for self harm or harm to others and history of suicidal behaviour.
Evaluation of functional impairment in ability to work and in family and social
relationships. Determination of the optimal treatment setting to attain assessment and
treatment objectives and importantly to maintain patient safety and minimise risk to self
neglect, risk to self harm and harm to others. Treatment setting ranges from the least
restrictive community and outpatient clinic to inpatient treatment under voluntary or
involuntary conditions. (APA Treatment Recommendations, 2000).
Consent to ECT
Valid consent to ECT is required unless common law or statue provides authority to
treat without consent when treatment is in the patient’s best interest i.e. necessary to save
life or prevent deterioration or ensure an improvement in physical and mental health
.Consent may be withdrawn by the patient at any time. If the patient refuses or is
incapable of giving or withholding consent to ECT, a second opinion of a specialist
colleague should be obtained and the patient’s relatives are consulted before a decision is
made to give ECT. A patient who is ill enough to require ECT, is almost certainly unable
to give fully informed consent.
Acute Treatment
ECT is particularly indicated for patients with severe depressive disorder associated with
greater severity ( in terms of intensity , frequency, and duration ) of symptoms including
the presence of psychotic feature (delusional depression) or catatonic symptoms, and the
urgent need for improvement in those with high suicide risk or those who are at risk of
serious physical deterioration. Under these circumstances, ECT is the treatment of first
choice with or without pharmacotherapy with antidepressants and anti-psychotics when
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indicated. Prior history of improvement with ECT and patient preference for the
treatment are also important considerations.
The evidence base
A recent systematic review and metanalyasis of randomised controlled trials and
observational studies of the efficacy and safety of ECT in depressive disorders (UK ECT
Review Group, 2003) reported the following findings:
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ECT versus simulated ECT – ECT was significantly more effective than simulated
ECT in the reduction of depressive symptoms and no difference in premature
discontinuation from treatment for patients receiving ECT and simulated ECT.
Patients treated with ECT were better able to retrieve remote memories than those
treated with simulated ECT and had more recognition errors immediately after
treatment.
ECT versus pharmacotherapy – treatment with ECT was significantly more effective
than pharmacotherapy and discontinuation was significantly lower in the ECT group
than in the pharmacotherapy group.
Bilateral versus unilateral electrode placement – Bilateral ECT was more effective
than unilateral ECT in the reduction of depressive symptoms High-dose unilateral
ECT might be as effective as bilateral ECT and causes fewer adverse cognitive
effects. Bilateral ECT was associated with impairment in anterograde memory
impairment within seven days of the end of the randomised phase of treatment but
no long term cognitive impairment.
Frequency of ECT – ECT administered once a week, twice and three times a week
had similar effects on depressive symptoms and no difference in discontinuation of
treatment but more frequent ECT lead to more cognitive impairment.
Dose of electrical stimulus – high dose ECT lead to greater reduction in depressive
symptoms, but was associated with more impairment in anterograde memory but not
in terms of personal memory.
Stimulus wave form – brief pulse and sign wave ECT were equally effective with
some indication that patients receiving brief pulse ECT recovered more quickly and
had better recall of word associates learned shortly before the treatment than did
those receiving sign wave ECT.
A meta-analysis of the efficacy of ECT in depression deriving from 15 randomised
controlled trials (RCTs) showed ECT to be superior to pharmacotherapy and simulated
ECT, with the presence of psychotic symptoms predicting better response to ECT (Kho
et al, 2003). The report found no evidence for a superior speed of action of ECT or for
a difference between sine wave and brief pulse stimulation. ECT has been shown to be
more effective in delusional than in non-delusional depression (Meyers et al, 2001,
Birkenhager et al, 2003).A recent Cochrane Review assessed the efficacy and safety of
ECT compared to simulated ECT or antidepressants in the depressed elderly (Van der
Wurff et al, 2003). Only 3 trials could be included and all had methodological
shortcomings. The results indicated the efficacy of ECT compared to simulated ECT,
but the efficacy of unilateral over bilateral ECT and safety could not be assessed
adequately. Older age confers a greater likelihood of achieving a remission with bilateral,
dose-titerated, continuation ECT in comparison with continuation pharmacotherapy
(O’Connor et al, 2001).
The NICE Review (2003) of data from 90 RCTs of ECT in depressive disorders
concluded that
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real ECT (where electric current was applied) is more effective than simulated
ECT (no electric current was applied) in the short term
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bilateral ECT is more effective than unilateral ECT.
raising the electrical stimulus above the individual’s threshold supported the
efficacy of unilateral ECT at the expense of increased cognitive impairment.
ECT was more effective than antidepressants notwithstanding the variable quality
of RCTs and the inadequate doses and duration of antidepressants that were used
in many of the trials
ECT is associated with cognitive impairment, particularly in those who had
bilateral ECT or unilateral ECT applied to the dominant hemisphere
cognitive function does not last more than six months from the administration of
ECT
there is no evidence that ECT is associated with greater mortality than that
associated with the administration of general anaesthetics. Studies that use
brain/scanning techniques showed no evidence that ECT causes brain damage.
there is no evidence to suggest that the benefits and safety of ECT are agedependent.
there are no complications of ECT in pregnancy but the risks should be balanced
against refusing antidepressant.
Continuation pharmacotherapy after ECT
High relapse rates of depression have been consistently reported after remission with
ECT. Five controlled trials have demonstrated the efficacy of continuation treatment
with antidepressants and lithium in reducing relapse after remission with ECT (AbouSaleh and Coppen, 1988). Further RCTs have demonstrated the efficacy of continuation
treatment with imipramine and paroxetine in relapse prevention in such patients
(Lauritzen et al, 1996). Nortriptyline monotherapy and its combination with lithium has
also been shown to be superior to placebo over 6 months in preventing relapses in
unipolar depression following remission with ECT (Sackeim et al, 2001) .
Schizophrenia
A Cochrane Review assessed the evidence for the efficacy of ECT in clinically
meaningful benefits in patients with schizophrenia and whether variations in the practical
administration of ECT influences outcome (Tharyan and Adams, 2002). The Review
included 24 trials and 46 reports and showed the following:
 Fewer patients remain unimproved with ECT, with less relapses and earlier
discharge than patients treated with placebo or simulated ECT
 limited data indicated visual memory impairment with ECT compared with
simulated ECT
 ECT is less beneficial than antipsychotic medication
 continuation ECT added to antipsychotics is superior to antipsychotics alone but
is associated with more memory impairment.
ECT has been shown to have good short-term effects and be safe in middle aged and
elderly patients with intractable catatonic schizophrenia (Suzuki, et al, 2003) and in
treatment-resistant schizophrenia (Tang and Ungvari, 2003).
In schizophrenia, the NICE Review (2003) of the data from 25 RCTs indicated that ECT
may be effective in acute episodes of certain types of schizophrenia and reduces the
occurrence of relapses. However, the results were not conclusive and the design of many
of the studies did not reflect current practice. Moreover, there are no RCTs of ECT
compared with antipsychotics. Furthermore, studies that include patients with treatmentresistant schizophrenia had not reported the use of clozapine. The review concluded that
ECT alone is not more effective than antipsychotic medication but that the combination
of ECT and pharmacotherapy may be more effective than pharmacotherapy alone
although the evidence is not conclusive.
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Mania
The NICE Review (2003) of 4 RCTs indicated that ECT may be of benefit in rapid
control of mania and catatonia, a suggestion that is supported by the results of
observational studies. Overall however, it concluded that the evidence for the
effectiveness of ECT and for the determination of the most appropriate therapeutic
strategy is inconclusive. In contrast, a recent literature review of continuation and
maintenance ECT in treatment-resistant bipolar disorder reported good evidence for
efficacy (Vaidya et al, 2003).ECT is indicated in severe and prolonged mania (excitement,
delirium, psychosis, or rapid –cycling manic states), especially when the anti-manic
medications (lithium, neuroleptics) have been relatively inefficient (Mukherjee et al.
1994). It seems that the NICE review has been restrictive in the studies it considered and
the conclusions drawn from them.
Other indications
In certain rare conditions ECT is widely considered to be a first-line treatment choice.
Catatonia, i.e. marked abnormalities in the overall level of motor activity, either on the
stuporous, or the excited form, can be manifested in the context of mood disorders and
schizophrenia. Since this condition constitutes a state of psychiatric emergency and
although some pharmacological interventions (such as benzodiazepines, barbiturates)
may have some effectiveness, ECT should be considered early in the treatment plan
(McCall, 1992). ECT should also be considered as a life-saving treatment for certain cases
of neuroleptic malignant syndrome- a condition sharing some similarities with catatonic
stupor- particularly if conservative treatments (direct dopamine agonists, dantrolene
sodium, etc.) have failed to control the condition within a few days (Trollor & Sachdev
1999). ECT has been occasionally employed in several non-mood disorder diagnosesincluding alcoholism, anorexia nervosa, OCD, dementia, personality disorders and
Parkinson’s disease (McCall, 2001) but the current state of the evidence does not allow
the general use of ECT in these conditions. It must be noted that when ECT is used in
special population groups, such as during pregnancy, in older people, and in children and
young people, and in view of its possible risks, clinicians should exercise particular
caution (National Institute for Clinical Excellence,UK, 2003)
Risks
The mortality associated with ECT is similar to that associated with minor procedures
involving general anaesthesia (1/100,000 per treated patients), with death almost
exclusively due to cardiac complications. However, with adherence to administration
guidelines, serious cardiac complications such as myocardial infarction, ventricular
fibrillation, and ruptured aneurysms- are rare even in patients with pre-existing cardiac
disease (Zielinsky et al 1993). Cognitive disturbances in the acute use of ECT retrograde
and anterograde amnesia and confusion are in general transient and reversible and in
most cases do not pose a major or persistent clinical problem. Further, controlled brain
imaging studies failed to provide any evidence that ECT causes brain damage (National
Institute for Clinical Excellence, 2003). However, the issue of cognitive dysfunction in
the case of continuation and maintenance ECT is still open to inquiry. In addition
cognitive dysfunction associated with ECT, even though difficult to differentiate at times
from the effects of psychopathology itself, is extremely distressing to certain patients and
should always be followed closely. A recent systematic review of studies of patients’
perspectives on its benefits and its effects on memory, showed that the perceived
benefits were less in patient led studies than clinician led ones .Moreover at least one
third of patients reported significant memory loss after treatment with no difference
between patient and clinician based studies (Rose et al, 2003).
Contra-indications
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There are no known absolute contra-indications to ECT but certain relative contraindications do exist: Brain tumour or cerebral infarction, history of myocardial infarction
or cardiac arrhythmias, cardiac pacemakers, aneurysms, retinal detachment,
pheochromocytoma, and pulmonary diseases are among the potentially dangerous
conditions where the use of ECT is considered high risk and requires additional
precautions (Stevens et al 1996).
Practical considerations
There are no grounds for administering unmodified (no anaesthesia) ECT .Anaesthesia
for ECT involves pre-ECT assessment and investigations to consider contraindications,
preparation, premedication, anaesthetic induction agents, muscle relaxants, ventilation
and recovery from anaethesia. The routine medications administered are atropine (not
universally employed by the clinicians) to prevent vagotonic bradycardia, succinylcholine
as muscle relaxant, and pentothal, methohexital or etomidate as hypnotics.
Six to 8 sessions is the average number of treatments for depression (up to 12 or more,
on occasion, if there is no clinical improvement), while for mania the number is 8-12
(usually up to 16). Patients who are reported to respond fast (after 6-8 treatments) and
relapse fast, may suggest a necessity to switch early to continuation therapy (Abrams and
Swartz, 1992). Three times a week ECT (as used in the USA) as opposed to twice a week
schedule (as used in Europe) are similar in effectiveness. Patients progress should be
monitored after each treatment to assess efficacy and side effects. ECT should be
continued until clinical improvement is observed. Regarding the electrical stimulus the
best results are expected, as a general rule, with brief-pulse square wave, electrical doses
about 2.0 to 2.5 times higher to the seizure threshold (rather than doses around the
seizure threshold) and with bilateral ECT as opposed to unilateral ECT electrode
placement. However, optimal electrical dosing and electrode placement should be
individualized for each patient. Monitoring seizure activity is achieved by simply timing
the convulsion and the use of the cuff technique .The cuff technique unlike the timing of
the convulsion is not affected by muscle relaxants. EEG monitoring is the most direct
assessment of cerebral seizure activity and is useful when total paralysis is desired.
There are indications that continuation of ECT treatments at biweekly or monthly
intervals over 4 to 6 months following acute ECT administration, could be beneficial
sustain the treatment benefits. The systematic studies to evaluate these forms of
treatment are currently underway and no conclusive data are available as yet. Clinical
judgement and prudence are recommended in the use of these outpatient forms of ECT.
Important components of good practice in ECT are the education of patients, their
carers and the general public. Fact sheets for patients and carers would facilitate their
cooperation and allay understandable concerns. Public education on ECT is an important
component of professional bodies antistigma campaigns.
Administration of psychotropics during ECT
There is controversy regarding the co-administration of antidepressants and ECT. On
one hand the discontinuation of a failed antidepressant seems reasonable. Yet, a
synergistic effect cannot be ruled out as no data are available, neither the possibility of
withdrawal symptoms upon the abrupt antidepressant discontinuation (McCall, 2001).
Reviews of the interactions of ECT and other psychotropic drugs find some interactions
to be synergistic (neuroleptics in psychoses but not in depression), some antagonistic
(benzodiazepines and anticonvulsants), and some eliciting adverse reactions, such as
confusion (lithium) or cardiovascular complications (MAOI). The co-administration of
compounds such as thyroid hormones, pindolol, or caffeine, as augmentation strategies
during ECT, has not reached a general consensus.
Perspectives
After seventy years from its introduction, convulsive (and electroconvulsive) therapy
represents an effective intervention for several disorders. Regarding its future
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perspectives, optimization of the treatment procedure as well as the estimation of its
value for continuation and maintenance treatment remains of high priority. On a
theoretical level, the elucidation of its mechanism of action is expected to advance our
knowledge not only in treating depression but in elucidating the nature of the illness
itself.
Guidance and Recommendations
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ECT should only be considered after a comprehensive assessment and careful
diagnosis of the illness with the assessment of the balance of potential benefits
and risks including: risks of anaesthesia, physical condition, anticipated adverse
events, particularly cognitive impairment; and the risk of not having treatment.
ECT should only be administered after informed consent is obtained from
patients with capacity. Appropriate guidelines for patients with impaired capacity
should be adhered to.
With these provisos, ECT is strongly recommended as a first line acute treatment
for severe depressive disorder particularly depressive disorder with psychotic
symptoms (delusional depression), depression with high risk of suicide, harm to
others, self neglect and physical deterioration. ECT is effective in the treatment
of antidepressant-resistant depression and the rapid control of symptoms of
catatonia and prolonged or severe manic disorder.
ECT is associated with high rates of relapse following remission of depressive
disorder and it is strongly advocated to use continuation pharmacotherapy with
antidepressants or lithium for a period of 16-20 weeks following remission of the
illness. ECT is not recommended for the general treatment of schizophrenia.
There is insufficient evidence for the long term benefits and risks of
maintenance ECT for depressive illness.
Careful consideration of risks is advocated in pregnant patients, older people and
children.
ECT is a safe treatment but has adverse effects on the short term memory and
long term recovery of memory impairment is the rule. Bilateral ECT is associated
with more cognitive impairment compared with unilateral ECT applied to the
non-dominant hemisphere of the brain. The frequency of ECT and other
parameters have little impact on its efficacy.
Acknowledgement
We are grateful for the endorsement and comments of members of the Section on the
first draft and this statement, particularly those from C L Katona and C P Freeman.
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