Paper presented at the 11th National Public Health Colloquium held at the Summit Hotel Subang Jaya 21-22 September 2004 by Prof Dr Omar Hasan Kasule, Sr. MB ChB (MUK), MPH & DrPH (Harvard) Deputy Dean Faculty of MedicineUIA Kuantan omarkasule@yahoo.com

This paper is makes 2 assumptions. The first assumption is that in an ideal situation ethics should be included within the law. The second assumption is that the ethical principles of biomedical research apply to public health with few modifications. Legal guidelines for public health research can be derived from the Purposes of the Law[i]. Public health research must fulfill and not violate the 5 purposes of the Law. It must protect, preserve, and promote the 5 purposes of human society: (a) morality, (b) life and health, (c) progeny (d) human intellect, and (e) property.


Five ethical issues have traditionally been considered in public health research: ethical approval, balance of individual and community rights, balance of benefits vs risks, informed consent, privacy and confidentiality, and conflict of interest. Study interpretation and communication of study findings is currently taking center stage as the leading ethico-legal issue due to widespread reporting and discussion of results of public health research in the mass media.


A study involving humans must get approval from a recognized body after fulfilling scientific criteria published in 1992 by the Council for International Organizations of the Medical Sciences under the title ‘Guidelines for Ethical Review of Epidemiological Studies’. The assumption (not always true) is that a body of responsible individuals is less likely to make mistakes or commit outright corruption whereas an individual is more wont to follow whims and personal interests. Public health research and intervention may lead to conflict of individual rights and community rights necessitating restriction on individual rights in the public interest. The Law in general allows public interest to take precedence over private interest provided this does not lead to permanent abrogation of individual rights. It should however be appreciated that the individual is part of the community and benefits directly from any research or intervention that is of community benefit. Public health research interventions carry risks and costs that must be balanced against the benefits. In general the benefits must outweigh the risks. Research is not undertaken if the risks equal in worth to benefits under the Principle of the Law that prevention of harm takes precedence over assurance of benefit.


The doctrine of informed consent requires that subjects must be free to participate in the study, abstain from participation, or elect to withdraw from the study at any stage. Informed consent is based on the legal principle of intention. Of all players in a research project, it is the individual research subject who is most concerned about personal safety since normal adults never willingly subject themselves to harm. He/she should therefore have the last word about participation or non-participation.


Public health researchers must respect privacy and confidentiality. Data collected in  public health research is reported in the aggregate without personal identifiers. Personal data cannot be released to any third party without consent of the subject. In this era of database networks with a lot of personal information about individuals and the increasing ability to link records will increasingly make the task of maintaining privacy and confidentiality of research findings difficult. One may have to contend with criminals who hack computers, steal, and sell information. Confidentiality is breached legally if the data is subpoenaed by a court of law when public interest takes precedence over individual rights. It is also breached when intervention becomes necessary to protect life and health.


Public health researchers can find themselves in situations of conflict of interest when their findings please some parties and annoy other parties. Public health researchers employed in academia can work relatively independently with few instances of conflict of interest but those working in industry are controlled by vested interests. Walking the tight-rope between conflicting interests is easier said than done. Some researchers are bound by restrictions on publication of their findings. Some have no such restrictions to start with but may suffer adverse consequences such as losing their jobs after publication of findings that do not please the employer.


Public communication of research findings raises serious ethical and legal issues. It is an ethical obligation to report research findings to subjects so that they may take measures to lessen risk. Risk reports that are not yet confirmed can be picked up by the media that report it in a sensational way that that ignores underlying uncertainties. Public health interventions have often been undertaken on the basis of incomplete and sometimes conjectural evidence. This is understood by the professionals who will modulate their zeal in intervention according to their degree of belief in the empirical evidence. However the public does not have the benefit of evaluating the evidence and often learns only the media headlines with much resultant confusion.


The following are examples of controversial findings that created confusion when reported in the mass media. MacMahon et al 1981 found that coffee causes pancreatic cancer whereas Feinstein et al. 1981 found that coffee did not cause cancer. Barefoot et al. 1983 found that type A personality was associated with heart disease but Shekelle at al. 1987 found that it was not. Vegetable-derived margarine had been thought to be good for the heart but Willet and Asherio 1994 found that it was bad for the heart. Falck et al 1992 found that pesticides caused breast cancer whereas Krieger et al 1994 found that they did not. Steinberg et al 1991 found that estrogen replacement therapy causes breast cancer whereas Kaufmann et al 1984 found that it did not. Beta carotene thought to prevent cancer was found by Omenn at al 1996 to cause cancer. Miller at al 1989 found oral contraceptives to cause cancer but the Cancer and Steroid Hormone Study Group of 1986 found that it did not[ii]. These findings were discussed by the general public in the media with much resultant confusion.


Epidemiological evidence is different from legal evidence but fate sometimes determines that the two meet in a court of law. Epidemiological evidence has few certainties; it is all probabilistic and is concerned with populations. Legal evidence on the other hand requires a higher level of certainty and is individually-based. Public health practitioners are surprised when their expert evidence is the basis for criminal or civil conviction. Epidemiologists are increasingly being called as expert witnesses in suits against tobacco fast food companies. The courts expect make definitive statements about causality which goes against their usual professional discussions when they report effect measures and then discuss bias and other factors if invalid or imprecise findings. 


The underlying problem is certainty of research findings. The Law recognizes 4 levels of decreasing certainty. The highest level is that of absolute certainty, yaqeen, which is  100% truth with no doubt at all. This level of certainty is not obtainable in empirical research that is based on imperfect often confounded observations that are both relative and probabilistic. Demanding absolute certainty will wipe out the whole public health profession because interventions are always based on a balance of probabilities. The next level of certainty of that of predominant conjecture, ghalabat al dhann, in which empirical evidence strongly one proposition over another one after taking into accounting the 3 main causes of bias (confounding, misclassification, and mal-selection). Some public health interventions are based on this level of evidence. The third level of certainty is conjecture, dhann, in which we have no clear-cut evidence but we can see a trend favoring one of 2 competing propositions. Most public health interventions especially in health education are undertaken at this level of certainty. The fourth and lowest level of certainty is pure doubt, shakk, in which the best available evidence cannot enable us favor even in a small way one of 2 competing propositions. We normally should not undertake any public health interventions.


There are some legal principles that can guide us in situations of uncertainty. When a given public health intervention is shown in practice to have some degree of effectiveness, it should be treated as a working modus vivendi until new information is obtained to necessitate its change. This provides for stability and a situation of quasi-certainty without which practical interventions will be taken reluctantly and inefficiently. This conclusion is based on the principle of the Law that a certainty cannot be voided, changed or modified by an uncertainty[iii]. When an assertion is an established truth, it should not be changed by a mere doubt being raised about all or some of its components. Existing assertions should continue in force until there is compelling evidence to change them[iv]. An existing phenomenon whose origin or cause is not known should be left as is until there is evidence to the contrary[v]. This principle protects against unnecessary public health interventions in long-standing anomalies or deformities that do not appear to cause any discomfort. Established medical procedures and protocols are treated as customs or precedents. What has been accepted as customary over a long time is not considered harmful unless there is evidence to the contrary[vi]. All these principles in general favor a conservative approach in public health interventions. A new event is considered of recent occurrence unless there is evidence to the contrary[vii]. An acquired attribute or change is not accepted as normal unless there is compelling evidence[viii].


Disclosure of research findings also raises ethical and legal issues. Research subjects have a right to know the conclusions from the research and how it impacts on their risk profile. The problem of interpretation arises because they may take the conclusions as definitive and not appreciate the shakiness of the evidence on which they are based. They may suffer equally from consequences of false negatives or false positives.


Ideally public health research should be reported in professional journals read by professionals who have the ability to evaluate the underlying evidence. Unfortunately the media in their eagerness for sensational news report half-truths that lead to much public confusion. At a moral level the media reporting of the negative (which sells newspapers) may lead to glorifying public health evils such as sexual promiscuity, alcohol and tobacco addiction, violence et

[i] Referred to as maqasid al shari’at

[ii] Ross C Brownson and Diana B Petiti: Applied Epidemiology: Theory to Practice. OUP New York and Oxford 1998, page 330)

[iii] al yaqeen la yazuulu bi al shakk

[iv] al asl baqau ma kaana ala ma kaana

[v] al qadiim yutraku ala qadamihi

[vi] , al qadiim la yakuun dhararan

[vii] al asl idhafat al haadith ila aqrab waqtihi

[viii] , al asl fi al umuur al ‘aaridhat al ‘adam

ęCopyright Professor Omar Hasan Kasule, Sr Septemer 2004