The authors wish to acknowledge the assistance of the following in the preparation of this manuscript: Frederick T. Melges, M.D., and Jared R. Tinklenberg, M.D. (Stanford University Medical Center), and Margaret Peterson, M.D. (University of Nebraska College of Medicine).

 

THE DRAMATIC INCREASE in the use of marijuana in this country has cut across all segments of our population, including that of young professionals (1-4). The controversy over the effects—harmful and beneficial—of the drug has led us to study the attitudes of future physicians concerning cannabis and its use. Our inquiry was spurred by a recent report revealing that 73 percent of University of California law students had broken the law by smoking marijuana (2). Prospective doctors, like law students, will play a key role in shaping society's position concerning the use of marijuana. Medical students' experience with marijuana will thus not only influence their own opinions, but also the opinion of society as a whole.

 

We surveyed the attitudes regarding the use of cannabis by students at four medical schools in different geographic regions during the spring of 1970. Our studies of marijuana use focused on the following questions:

 

1. What are the patterns of past, present, and projected use of marijuana by medical students?

 

2. What medical opinions do these future physicians have concerning marijuana and how do these opinions relate to their marijuana use?

 

3. What sources of information do medical students value in forming their opinions of marijuana?

 

4. How might marijuana use be expected to change if medical understanding of or legal sanctions against the drug change in the future?

 

Method

 

We distributed questionnaires to students in four widely separated medical schools, including one on the West Coast, two on the Eastern seaboard, and one in the Midwest. None of these schools will be identified by name, nor will bodies of data be identified as to region of origin.

 

Questionnaires were sent to all students in these four schools; included with each was a cover letter that stressed the importance and confidential nature of the project and stated that several schools were being surveyed at the same time. All questionnaires were strictly anonymous and were returned either into a locked chest near the student mail boxes or by mail. Since respondents were not identifiable, no follow-up of nonrespondents was attempted.

 

We began distributing the questionnaires in January 1970, and retrieval of responses was complete by April 1970. To increase the likelihood of a large return, we made the questionnaire brief. The nature of the questions asked will be presented along with the data.

 

Results

 

There were 1,063 questionnaires returned of the 1,708 that were distributed at the four medical schools. The rate of return from all schools combined was 62 percent; it varied from 57 percent to 65 percent.

 

Overall, 70 percent (734) of the respondents indicated that they had been present while cannabis was being used, 50 percent (529) revealed that they had tried the drug at least once, and 30 percent (317) identified themselves as current users (see table 1). Significantly, 50 percent (528) of these students had never used cannabis; 21 percent (215), though present when it was being used, had chosen to abstain.

When asked to indicate their medical opinions, 46 percent of our respondents indicated that the use of cannabis should be restricted according to its strength, and 23 percent thought that it was harmless and should be available without restriction; only one percent responded that there were no medical considerations (see table 2).

 

Overall, these students ranked peers (55 percent), professional reading (54 percent), mass media (44 percent), personal experience (33 percent), medical school teaching (23 percent), and authority figures (23 percent) as valued sources of information in arriving at their medical opinions (see table 3).

 

Single students showed greater exposure to marijuana (81 percent) than married students (63 percent) and also indicated greater past use of cannabis (58 percent and 46 percent, respectively). The age ranges in our study (21 to 26) did not reveal a difference in any categories of users.

 

Those persons who have been using marijuana longest appear most likely to be using it currently. Of those who first used cannabis in 1965 (N = 43), 79 percent indicated current use. There was a steady decrease for subsequent years: 1966 (N = 100): 76 percent; 1967 (N = 125): 65 percent; 1968 (N = 89): 52 percent; 1969 (N = 109): 38 percent. Of the 115 respondents who indicated that they have used marijuana over 100 times, 93 percent said they were using it currently.

 

The factor that showed the highest correlation with the respondent's experience with cannabis was the medical school he attended. Schools A and C had very similar patterns—high exposure to marijuana use, greater past use, and more current users, but lower numbers of those who never used it and fewer abstainers (see table I). More students at schools A and C rated cannabis as harmless, but high proportions at both A and C thought its use should be restricted according to the strength of the cannabis (see table 2). Students from schools A and C ranked professional reading and peers as the most valued sources of information in formulating their medical opinions.

 

School B had the lowest proportion of persons who had been exposed to marijuana (35 percent), who had experimented with it (17 percent), and who were currently using it (six percent). Only six percent of the respondents from this school thought that cannabis was harmless and should be available without restrictions, 23 percent thought it should be used only for research, and 19 percent had no opinion. Professional readings, the mass media, medical teaching, and peers were of nearly equal rank as valued sources of information. The importance of personal experience was low in this group (ten percent).

 

Our findings for school D were near that of the average for the four schools (see table 1), but this school had the highest proportion of abstainers (28 percent). Nearly half of this group believed that cannabis should be restricted according to strength, and 21 percent felt it was relatively harmless. They valued professional reading and peers as their most important sources of information. This group tended to rate medical school teaching higher than did respondents from schools A and C.

Our respondents' predictions of their use of cannabis in the future, based on four hypothetical contingency situations, appeared to be determined by their past experience with the drug. The four contingencies were:

 

1. Assuming that the legal status of marijuana remains unchanged and that marijuana is found to be totally harmless and as good a euphoriant as alcohol, would you expect your use of marijuana to change; how?

 

2. Assuming that the legal status of marijuana remains unchanged and that marijuana is found to be as good a euphoriant as alcohol with long-term effects identical with those of cigarette smoking, would you expect your use of marijuana to change; how?

 

3. Assuming that your medical opinion of marijuana remains unchanged and that the legal penalty for marijuana use is reduced to the level of a misdemeanor, would you expect your use of marijuana to change; how?

 

4. Assuming that your medical opinion of marijuana remains unchanged and that legal sanctions against marijuana are reduced to penalize only illegal behavior while under the influence (as is now the case with laws concerning alcohol), would you expect your use of marijuana to change; how?

 

Overall, the four schools responded similarly to the hypothetical situations (see tables 4 and 5). That is, the greatest upward change in cannabis use occurred with hypothetical situation 4, then 1, then 3, then 2. For situation 2, the net changes in projected use approached zero, though the groups varied somewhat. When we divided the respondents from each school into "users," "experimenters," and "never-users," we found considerable variation within each school.

 

Table 4 shows the potential marijuana users among the experimenters and never-users for each contingency. If the legal sanctions against marijuana use were considerably relaxed, some never-users predicted that they would become users, but most never-users did not expect to become users in any of the projected situations. The experimen ters indicated considerably more interest in using marijuana in all contingencies. If only aberrant behavior were penalized, a majority of the experimenters would increase their cannabis use. In contrast, if cannabis were found to have long-term effects equivalent to those of cigarettes, relatively few experimenters would resume cannabis use.

 

In almost all cases, a majority of the users would maintain their present level of marijuana use regardless of the projected conditions (see table 5). A small percentage would decrease their use in each case (except in school B, which had only 12 users), with a larger group indicating an expected increase in usage. This pattern was changed in contingency 2, which had a greater proportion of respondents expecting to decrease their use.

 

Discussion

 

Overall, slightly more than 50 percent of our respondents had used cannabis. This figure was higher than those in other published studies of high school and college students (5-8). The only studies showing equivalent use were those of the University of California law students (2) and of the soldiers in Viet Nam (9). Cannabis use by the respondents in this study was more related to the medical school attended than to age, sex, or marital status. The social pattern of the geographic area in which each school was located may have influenced the respondents' use of this drug. Exposure (presence during use of the drug by others) appeared to be significantly related to current and past cannabis use. In this study, the percentage of abstainers remained rather corstant.

 

Students from schools with the highest number of current and past users tended to view cannabis as relatively harmless. They felt, however, that its use should be restricted according to its strength. They ranked professional readings and peer group pressure as important sources of information in forming their medical opinion of the drug.

 

At the two schools with the highest number of users, students gave medical school. teaching a low ranking as a source of information.

A

t one of these two schools, however, authority figures held a moderate position in terms of significant influence.

 

When the students who identified themselves as users were asked to predict their use of cannabis in the four hypothetical situations, their responses were varied. More than half of the current users expected to continue their current level of use of cannabis unless its legal status changed to that of alcohol, in which case their use was expected to increase. A significant number of users planned to decrease their use if medical research reveals that cannabis has effects similar to those of tobacco. Among the users, cannabis use was expected to remain unchanged in most of the situations we outlined.

 

The number of students who were not currently using cannabis but who had used it in the past varied from one-tenth to one-quarter of our respondents, with higher proportions in the schools with greater exposure and greater past and current use. The experimenters indicated considerably more interest in using marijuana in all contingencies. There was a marked increase of cannabis use predicted in all contingencies except the second (medically like cigarettes, legality unchanged). If only aberrant behavior were penalized, then more than 50 percent of these future physicians would increase their cannabis use, with students in school D indicating the greatest magnitude of change (82 percent). In contrast, if cannabis were found to have long-term effects equivalent to those of cigarettes, only one-fifth would resume cannabis use.

 

Slightly less than 50 percent of our respondents had never used cannabis. Schools B and D showed the highest percentage of never-users. Never-users fell into two categories; the never-exposed and the abstainers. The never-exposed group, which is represented by school B, had the lowest number of past and current users. The number of experimenters was well below that in the other schools, and the number of abstainers was equal to the average for the four schools. The never-exposed students tended to view cannabis as being more harmful, with a significant number of respondents indicating that cannabis should be used for research only. This group also had the greatest number of respondents with no medical opinion. Respondents from schools B and D valued medical school teaching more highly than did respondents from schools A and C.

 

The highest percentage of abstainers was found at school D. Abstainers tended to view marijuana as harmless, but they chose not to use it when they were exposed to it. This group viewed professional reading, medical school teaching, and the mass media as being more influential than did the respondents as a whole.

 

The overwhelming majority of the never-users did not intend to use marijuana regardless of the contingency postulated. A small portion would indulge if medical science proved cannabis harmless. A larger portion would probably use it if its legal status were comparable to that of alcohol.

 

Summary

 

Four medical schools in different geographic locations were studied. The medical students were divided into three categories: users, experimenters, and never-users. There was a difference in use according to the social patterns of the geographic area rather than according to age, sex, or marital status. In addition, medical opinion of marijuana varied geographically. In those schools with a high percentage of marijuana use, professional readings and peer group use ranked as more important than did medical teaching. These students did feel, however, that there should be some way of assessing the strength of the drug.

 

The amount of current use could be expected to increase with a change in marijuana's legal status, provided that medical research does not reveal long-term cannabis use to have effects similar to those of cigarettes. The experimenters indicated more interest in marijuana use. The never-users, divided into the never-exposed and the abstainers, tended to view marijuana as more harmful and feel that its use should be restricted to research. Abstainers felt that cannabis use is harmless but did not choose to indulge. They might consider using it if there were a change in its legal status.

 

The results of this study indicated that there is a vast gulf between the position of the medical profession and the position of the medical students. Future studies on short-term and long-term effects need to be done, since this is one of the factors that influence its use. We, the authors, generally agree with the students we surveyed and strongly disagree with the position of established medicine (10, 11) concerning the use of this drug. To date, there have been no studies that can clearly relate any dangerous effects to most casual users of this drug in the quantities that are consumed in most social settings.

 

If medical authorities cannot convince medical students to refrain from using marijuana, persuading the population at large seems unlikely. If medical students, with their excellent intelligence, cannot be convinced, it behooves medical educators to wonder why. Perhaps student and educator both have something to learn and something to teach. We believe that medical research can provide the facts so that this dialogue may begin.

 

REFERENCES

 

I. Mechoulam R: Marijuana chemistry. Science 168:1159-1166,1970

2. Bass D: The pot-smoking UC law students. Sar Francisco Chronicle, Oct 27,1969, p I

3. Clark WH, Funkhouser, OR: Physicians and re searchers disagree on psychedelic drugs. Psychol ogy Today 3 (11):48-73,1970

4. Modern Medicine poll on sociomedical issues abortion, homosexual practices, marijuana, anc interpretive summary. Modern Medicine, Nov 3 1969, p 18-30

5. Mizner GL, Barter JT, Werme PH: Patterns of drug use among college students: a preliminary report. Amer J Psychiat 127:15-24, 1970

0. Blum RH and associates: Students and Drugs. San Francisco, Jossey-Bass, 1969

7. McGlothlin WH, Cohen SI: The use of hallucinogenic drugs among college students. Amer J Psychiat 122:572-574, 1965

8. lmperi LL, Kleber HD, Davie JS: Use of hallucinogenic drugs on campus. JA MA 204:87-90, 1968

9. Pot smoking in combat—Army study. San Francisco Chronicle, Apr 4,1970, p I

10. Council on Mental Health: Marijuana and society. JAMA 204:1181-1182,1968

11. Kolansky H, Moore WT: Effects of marijuana on adolescents and young adults. JAMA 216:486-492, 1971-