''Where you stand depends on where you sit.''
This saying usually applies to political issues, but it is also relevant to medicine. Consider the current controversy over the prescription of antidepressants to children, and the different reactions of British and American regulators and physicians.
After examining a series of 13 clinical trials including more than 2,300 children and adolescents, drug regulators in Britain strongly urged doctors not to use certain antidepressants, among them Paxil, Luvox and Zoloft, for childhood depression because the risk of self-harm and suicidal thoughts was judged to be too great.
In the United States, however, officials at the Food and Drug Administration, relying on the same clinical data, have yet to make up their minds on the safety issue, and doctors here continue to prescribe antidepressants to children in volume.
In Britain, 40,000 patients under 19 years old are taking antidepressants, mostly those in the class known as selective serotonin reuptake inhibitors, or S.S.R.I.'s, according to the Medicines and Healthcare Products Regulatory Agency. This compares with estimates of one million children and adolescents taking such medication in this country.
Adjusted for population, that means that American doctors are five times as likely as British doctors to prescribe antidepressants to children. Most British physicians consider psychotherapy, not drugs, to be first-line treatment for childhood and adolescent depression.
Why the different approaches? Much of the answer lies in contrasting medical cultures. ''The British think we overdiagnose and overtreat children,'' said Dr. David G. Fassler, a child psychiatrist at the University of Vermont College of Medicine.
Prof. Frank Furedi, a sociologist at the University of Kent in England, agreed. ''We are more cautious about medicalizing the problems of children,'' he said.
The same phenomenon can be seen in the treatment of attention deficit hyperactivity disorder. Despite clear benefits, physicians in Britain were slow to use Ritalin and other stimulants, in part because hyperactivity itself was considered very rare until well into the 1980's.
Meanwhile, American physicians were diagnosing hyperactivity in children in the late 1960's, and regarded stimulants as standard frontline treatment.
Americans' greater faith in medication in these situations may reflect an enthusiasm about technological progress.
''We in Britain are more skeptical of advances in general,'' said Dr. David Healy, a psychiatrist at the University of Wales College of Medicine and a critic of antidepressant use in children. ''For example, it took us longer to adopt imaging technology like CAT scans and M.R.I.'s as routine.''
Unquestionably, antidepressants have saved countless lives, but they also reinforce the existence of the very disease they are meant to treat. As Dr. Healy argued in his new book, Let Them Eat Prozac, when drugs are developed for a specific condition, rather than for a general state like stress, pharmaceutical companies end up marketing mental illnesses, not just pills.
''It is no coincidence,'' he said, ''that an explosive increase in diagnoses of depressive illness followed the development of S.S.R.I.'s.''
In the United States, the tendency to sell diagnoses gets an extra boost from direct-to-consumer advertising, which is banned in Britain.
In addition, patients in Britain have less choice among medications than they do in the United States. As Dr. Steven A. Schroeder, a former president of the Robert Wood Johnson Foundation, who once studied medicine in London, said, ''Patients have less power in Britain than they do here.''
Britain's National Health Service determines the medications that the government will purchase and that physicians will prescribe. Americans have more autonomy in choosing doctors and in negotiating treatments because they pay, either directly or through insurance.
The British, Dr. Schroeder said, seem to have a more modest sense of entitlement. ''There, the population is less demanding of treatment for behavioral and other problems,'' he said, ''and are less likely to seek help for such things as'' attention deficit disorder, chronic fatigue and impotence.
At the same time, in the United States, managed care, with its strong emphasis on cost-saving, creates its own demands. Pills are cheaper than psychotherapy, and so they are more popular.
''Initially, managed-care companies promoted psychopharmacology for depressed adults,'' Dr. Fassler said. ''Now there's more pressure to treat children and adolescents with medication. And more and more of the prescribing is being done by pediatricians as opposed to child and adolescent psychiatrists.''
All these factors help explain why British health regulators have a lower tolerance for risk, especially when benefits may be minimal.
Practically no one disputes that antidepressants are only minimally effective in children. Some children appear to be helped enormously--hence the many doctors who swear by these medications--but the studies indicate that on average, the advantage over placebo treatment is small. (The British exempted Prozac from their warnings, because the regulators concluded that there was more evidence for its effectiveness and safety in children).
The important issue, then, is whether antidepressants truly worsen the potential for suicide. The F.D.A. says it does not yet know the answer because in the clinical trials, minor episodes of self-harm and more serious episodes were lumped together under the umbrella term ''possibly suicide-related event.''
No distinction, for example, was made between young patients who took large overdoses of the drugs or who tried to hang themselves, and those who made superficial scratches on their arms. There were no actual suicides in the studies.
The F.D.A. has asked researchers at Columbia to reclassify the cases of self-harm to clarify their nature. In the meantime, the agency has issued strong warnings to doctors to closely monitor patients they are treating with these medications. This summer, the agency will weigh the potential risks of the drugs against the clinical benefits and presumably reach some conclusion.
In comparison, the British, through their different prism, see little need to pursue the question. Lacking a strong cultural investment in antidepressants, they have already decided that any risk of self-harm is too high.
Sally Satel, M.D., is a resident scholar at AEI.