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From the * Center for Epidemiology and Health
Research Berlin, Berlin, Germany; and
Strategic Business Unit Fertility
Control/Hormone Therapy, Corporate Strategic Marketing Male Health Care,
Schering AG, Berlin, Germany.
| Correspondence to: Dr Klaas Heinemann, Center for Epidemiology and Health Research Berlin, Invalidenstrasse 115, 10115 Berlin, Germany (e-mail: heinemann{at}zeg-berlin.de). |
| Received for publication July 29, 2004; accepted for publication November 2, 2004. |
But still knowledge on the attitudes and expectations in males concerning MFC is limited. About one-third of all couples worldwide rely on male-dependent contraception methods, and the importance of the male contribution has often been underscored (Ringheim, 1996; Drenman, 1998).
There have been many surveys about attitudes toward and practice of contraception in general, but only a few concerning males opinions (Keith et al, 1975; Davidson et al, 1985; Ringheim, 1993; Ezeh et al, 1996; Hulton and Falkingham, 1996; Drenman, 1998).
First impressions have been achieved in some clinical studies (Bebb et al, 1996; Handelsman et al, 1996; Merrigola and Bremner, 1997; Sjörgen and Gottlieb, 2001). A few surveys showed results on knowledge, attitudes, and acceptability of male fertility control (Grady et al, 1996). A recent one showed variability within countries and ethnic groups (Glasier et al, 2000; Martin et al, 2000).
Now an MFC method is at an advanced stage of development, and more extensive research on a multinational base has had to be conducted.
The MFC study was conducted in 9 countries and 4 continents, and over 9000 males were included.
Based on the data collected, this paper tries to describe factors associated with MFC and perceived positively and negatively and aggregate all the information into a potential characteristic of an MFC user as expected several years before a commercial drug is launched.
Materials and Methods
The methods used for the international survey have been published elsewhere
(Heinemann et al, 2005). In
brief, the objectives of the large cross-cultural survey were as follows: 1)
We prepared a comparative survey to provide details about the awareness,
attitudes, and acceptability of male fertility control in various methods of
administration on a multinational level. Some of the results have been
published elsewhere (Heinemann et al,
2005). 2) We analyzed determinants for differences among various
groups and described types of potential users in order to draw conclusions
concerning further studies.
A total of 9342 men aged 18 to 50 were recruited, based on population panels or quota samples. The participating countries were Argentina, Brazil, France, Germany, Indonesia, Mexico, Spain, Sweden, and the United States.
In Europe (except for Sweden) and North America, study participants were selected by a random sampling males aged 18 to 50 from existing community panels. These panels have been in wide use for years in the countries concerned; are representative of the overall populations with respect to age, sex, regional structure, and social status (eg, educational, income levels); and in some cases include medical history parameters as well. The methodology has been described elsewhere (Potthoff et al, 2004).
In Latin America and Indonesia, the study questionnaires were distributed by interviewers on the basis of a quota sample. Interviewers were sent from house to house in selected regions, recruiting men of the required age group who were willing to participate in this study. When a total of 1000 men had been interviewed in each country, the study was considered complete.
The survey was designed as a structured, standardized interview, with identical questions, answers, and sequences in all countries. All questions were multiple-choice, except for 2 open-ended questions.
The respondents were questioned about their knowledge of and their general attitude toward existing fertility control methods as well as toward a new male contraception method.
The field work started in waves in March 2002. Field work and data entry were completed by the end of June 2002.
The cleaned and validated data set was then transformed into an SPSS format, documented with variable labels and value labels, and consequently saved in a general SPSS file, where the access to the individual countries is made possible via a specific country code.
Factor analyses and cluster analyses were mainly carried out with the SPSS® for Windows 10.0 statistical package. Additionally, a STATA® 6.0 database was set up for other univariate and multivariate analyses.
Results
The sample description will be published elsewhere
(Heinemann et al, 2005). In
brief, The median age of the participants ranged from 29 years (Mexico) to 40
years (United States).
In all the participating countries except for Indonesia the vast majority of the respondents belonged to a Christian religion. Most of the Indonesian participants were Islamic.
The percentage of married or cohabiting respondents ranged from 82.1% (Germany) to 62.7% (Argentina).
The median number of children was 2 across all centers, but varied markedly between 1 and 20 in some countries.
Low education ranged between 7.7% (United States) and 61.3% (Germany) according to our definition (basic education or less). The highest education level (university level) was between 8.4% (Brazil) and 47.3% (United States). It should be stressed that this comparison is biased because of different educational classifications, which could not be overcome.
The proportion of the lower third income category (self-assessed) varied between 15% (France) and 55% (Argentina), for the upper third between 2% (Mexico, Argentina, and Indonesia) and 23% (United States).
The aim of this paper was to analyze determinants for differences among various groups and to describe types of potential users in order to draw conclusions about the need for specific studies. The statistical method of cluster analysis was used to derive the potential user groups based on the attributes which would—according to the respondents—positively or negatively influence the decision to use the new MFC method. To use the cluster analysis, the attributes used to create the clusters must not be intercorrelated. A factor analysis should be conducted in order to reduce highly correlated attributes to independent factors (Berekoven et al, 1993).
Factorial Analysis— The respondents were given a list with 14 parameters that could potentially have a positive influence on the decision to use a new MFC (eg, low side effects, increased libido, etc). They were asked to decide how important each of these parameters was. The same was done for 14 parameters with a potentially negative influence (eg, low efficacy, decrease in sexual potency).
Factorial analyses were performed to characterize patterns that positively or negatively influence the decision to use a new MFC method. Each of the mathematically determined factors describes variables that are closely linked according to the data. The 9 factors we found can be understood as largely independent constructs, explaining the total variance in the answers of all survey respondents with regard to the decision to use MFC. Factorial analyses done on the country level did not show material differences in the internal structure of the factors in the different countries.
Factors With a Positive Influence on the Decision to Use the New MFC Method— The aim of the factor analysis was to find the best describable groups of interlinked variables explaining an underlying common ground. For the 14 variables with a positive influence on the decision to use the new MFC, these best describable groups were found when 4 factors were created (Table 1). To make the difference among the 4 factors more visible, only high correlations with the respective factors (over 0.5) were depicted in Table 1. The aim of the naming process was to find a memorable name that describes the prominent patterns (variables of the questionnaire) characterizing the factor best.
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The sex-oriented pattern (first factor) involved all the variables related to sex life—such as enhancement of masculinity, sexual desire, improvement of sexual performance—and which variables would have a positive influence on the decision to use such a new MFC method. A potential positive impact was also observed for increase in muscle strength. However, 1 weighting of more than 0.5 was also found with factor 3 pointing at limited independence between factor 1 and 3.
The second factor was called pattern of independent safe and easy way of contraception. This factor embraces variables related to primary fertility control parameters such as efficacy, confidence in contraception, easy handling, quick onset time, reversibility, and few side effects. To a lesser extent, this factor is correlated with desired independence from the women concerning the contraception, which is more explicit with factor 3.
Factor 3 was named narcissist after the variables with the highest correlation. The positive influences that formed this factor include positive effects on the appearance of the user, namely, the positive influence on body frame and the increase of muscle strength.
Factor 4 of the positively influencing variables is the improvement of well being. This very general construct explains the second biggest share of the total variation in the answers and formed an independent factor. It did not really correlate with any of the other variables or overlap with the other factors.
Factors With a Negative Influence on the Decision to Use the New MFC Method— For factors with a negative influence on the decision to use the new MFC method, 5 factors have been determined even though it was a little harder to find good descriptive and memorable names for them. The exact numbers of the weightings that indicated a type of correlation of the 14 subquestions with the 5 calculated factors are shown in Table 2.
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The first factor (worry about safety and efficacy) involves attitudes concerning primary fertility control parameters that could negatively influence the decision to use such a new MFC method. A potential low efficacy and nonexisting long-term data on safety belong to these concerns, as well as fear of adverse side effects or fear of sexual hormones in general. The fear of tumors such as liver or gynecological tumors associated with hormones (Heinemann et al, 2000, 2003) played an increasing role in the last decade and led to several crises of hormonal treatment with extensive media coverage. This was also recognized by males.
Factor 2, religious-dominated refusal, consisted of negative attitudes due to religious reasons, due to objections against any male fertility control, and due to a general disapproval of drugs. The religious reasons showed the highest correlation to the factor. Whether the general disapproval of drugs and the negative attitude toward any male fertility control have a religious background is not clear, but they clearly belong to the same factor as the religious reasons. So a partly religious background was at least assumed.
In the third factor, which was named general rejection, attitudes are combined that concentrate more on the new male fertility control directly. Seeing a doctor regularly—which would be necessary with the new method—and the opinion that the already existing male contraception methods are good enough—a new method is not necessary—have a negative influence on the willingness to use such a new method. Another component of this factor was the attitude that contraception is the responsibility of the females. This was closely related to the opinion that there are enough other methods of contraception.
Two of the 14 subquestions were dealing with fears concerning the sex life—the possible negative impact on sexual satisfaction and on sexual potency. These 2 formed their own, fourth factor: sex-oriented fears.
In the last and fifth factor—not another drug please—2 subquestions were highlighted, both of which were related to a negative attitude due to an already existing high amount of medication that has to be taken. People who suffer from a chronic illness usually also have to take some drugs, which is obviously in opposition to use of a new MFC method.
Description of the Different User Types— The statistical method of cluster analysis was used to form different groups of users based on the role that single factors, which were created in the factor analysis, played for them. Here the goal is to identify homogeneous groups of people who are concerned about similar factors (Norusis, 1992).
The clusters were named based on the factors that had the highest positive means in the respective cluster. These data are shown in Table 3. Very distinct or even exaggerated names were chosen to better understand and distinguish these 3 groups. These names are intended to be of a descriptive nature and by no means offensive or assessing. It has to be stressed that the grouping in these clusters is not absolute—if a single participant belongs to 1 cluster, it does not mean the factors that make up the 2 other clusters do not play an important role for him. It just says his combination of statements better fits to the respective cluster than to the 2 others. One factor (not another drug please), for instance, has almost similar weights in 2 clusters of male participants.
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The Sex-Oriented Narcissist— The first identified cluster of respondents was called the sex-oriented narcissist. A total of 3534 participants were collected in this group due to similar knowledge, attitudes, and beliefs. The sexoriented narcissist is mainly interested in a positive effect on his sexual life (enhancement of libido, sexual performance, and satisfaction). To the same extent he is concerned that a new MFC method might interfere with his sex life or even threaten it. Additional factors that influence the member of this cluster are the potentially positive effects on the body (increase of muscle strength, positive influence on body frame) but also a rather disapproving attitude to male fertility methods and new drugs. The participants collected in this cluster would perhaps rather reject the new MFC method if it were only a contraception method, but accept it and be willing to use it because of any positive additional effects they consider as important.
The other factors that are used—due to their high positive means in the respective cluster—to describe the other 2 clusters also have positive mean value in this cluster. That means they also play a role in this user group—even though a minor one compared with the other ones.
The Religious Refuser— The second group was named the religious refuser. This cluster consisted of 1906 men. The religious refuser has a negative attitude toward any male fertility control method. He expresses religious reasons for the disapproval. Very high negative means could be found for the factors interest in own safe and easy way of contraception and worry about safety and efficacy, which shows that for the member of this cluster these topics are more or less unimportant.
The Informed— The third cluster was called the informed. A total of 2651 of the respondents belong to this group. The informed man is interested in his own safe and easy-to-use contraception, but also very concerned about potential risks and side effects as well as about a potentially low efficacy of the method. That they are concerned about potential risks and side effects is underlined by the third factor that influences the members of this cluster: not another drug, please. Higher negative averages were found not just for sex-oriented concerns but also for general rejection and religious dominated refusal—these attributes were rather unimportant for the informed group.
Geographical Distribution of Clusters— The informed group was found particularly in Europe, especially in Germany and Sweden (see Table 4). The group was of less importance in the United States. The 3 participating countries from South America differed significantly regarding the proportion of informed: Argentina had the same average distribution as the European countries, whereas in Mexico and Brazil the respective share was much smaller. In Indonesia the informed man basically did not exist; the proportion was just 2%. The religious refuser played the most important role there. This group was not very important in Europe. In the United States 23% of the participants belonged to this cluster. Argentina again showed the European distribution. In the 2 other Latin American countries the religious refuser was a more important group. The sex-oriented narcissist was particularly important in Brazil and less important in Germany and Sweden. In the other countries the share of this cluster lay between 42% and 50%.
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Educational Level— In the informed group a higher share of high educated participants (27%) could be found compared with the 2 other groups (14% in the sex-oriented narcissist and 13% in the religious refuser)—see Table 4. The share of the medium educational level in the 3 clusters ranged between 41% (the informed) and 46% (the religious refuser), the share of less educated respondents was 33% in the informed, 41% in the religious refuser, and 42% in the sex-oriented narcissist.
Income Level— Thirteen percent of the informed group belonged to the high income level group, whereas only 9% of the sex-oriented narcissist and 6% of the religious refuser had high income levels (see Table 4). The share of participants with a medium level income did not differ very much between the 3 clusters, but only 25% of the informed group belonged to the low income class as compared with 32% of the sex-oriented narcissist and 37% of the religious refuser.
Sources of Information— The physician was by far the most accepted information source (see Table 4). It was followed by journals. The rank and sequence of these 2 sources did not differ in the 3 clusters. Differences in the selection were noticeable only in the third, fourth, and fifth place. The informed and the sex-oriented narcissist groups rated the pharmacist as the third most important source of information whereas for the religious refuser friends were more important. For the informed group friends were the least important source; he would rather seek information on the Internet. For the religious refuser and the sex-oriented narcissist the Internet was least important.
Current Contraception— The percentage of men who are currently using any contraception method was much higher in the informed group than in the 2 other clusters (see Table 4). The share of men without a partner was about the same in each cluster (10% to 12%).
Willingness to Purchase the New MFC Method— The overall share of all study respondents who are willing or very willing to use the new method was 55% (see Table 4). When divided into the 3 different clusters, this willingness differed significantly. Sixty-four percent of participants who belong to the informed group stated their willingness to use the MFC method, whereas only 40% of religious refusers did so. The share of respondents who would disapprove of the method is more than twice as high in the religious refuser-group as it is in the informed group. The sex-oriented narcissist showed only slight differences to the pattern of the informed group.
Discussion
The overall willingness to use such a new MFC varied between 50% and 70%
across the participating countries, amounting to 55.2% on average. An earlier
survey (4-country study) found an acceptance rate of between 32% and 83%,
depending on the application form and the country
(Martin et al, 2000).
Nevertheless, acceptance rates may change when a clear profile and price of
the method are available.
A number of questions have to be asked in order to find out whether there are specific target groups for a new method among the end users. One has to determine which factors and attitudes lead to which acceptance level for the MFC and whether there are positive or negative interrelations in these attitudes. Is it possible to describe potential user groups based on these attitudes, groups who are more concerned about 1 set of interrelated attitudes than about others, and who therefore show differences in their willingness to use the new method? And, if so, are there any other differences in these groups which could help to develop specific strategies to reach them or to meet their desires?
Since it would become complicated and would probably lead to confusing results if 28 different variables, as collected in our study, were used to describe user groups, it was decided to do a factor analysis first. Factor Analysis is a statistical technique used to identify a relatively small number of factors that can be used to represent relationships among sets of many interrelated variables. It is used to identify the underlying, not-directly-observable constructs of entities such as freedom or creativity. These entities do not consist of variables that can be directly measured on scales, but can be described by different, directly observable variables. If the underlying dimension of these variables can be derived, the description and the understanding of these phenomena can surely be simplified (Norusis, 1992).
The purpose of the factor analysis was to create an explanatory construct for a set of empirical variables that helps to simplify the description of the concerns that will affect the decision-making process to use or to reject a new male fertility method. But it was not possible to describe potential differences or similarities of the participants only with these factors. Still it had to be figured out which of the factors were important to which of the respondents.
Using SPSS, different manual iterations were done to find factors that each include good describable groups of subquestions of both groups of variables separately.
The different groups of potential users could be determined using the SPSS® cluster analysis tool. These are the informed, the sex-oriented narcissist, and the religious refuser. The group affiliation is based on the different attitudes regarding factors that would positively or negatively influence the willingness to use the new male fertility control method. The group affiliation is not absolute but predominant; group members may also be concerned by factors that would belong to another cluster. This can be seen in the shares of willing-to-use participants in the 3 different clusters. The 3 groups differ significantly in their willingness, but all of them contain willing and unwilling men. Participants of this study belonging to the religious refuser do not form a homogeneous group, nor do the other groups. Not all the religious refusers would reject the new method; the members of this cluster only stated similar concerns, which were to some extent related to religion. This does not mean these men are not interested in the sex-related issues or the safety of the drug even though they stated the latter to be rather unimportant.
On the other hand, the members of the 2 other clusters are positively influenced by certain attributes, as for instance high efficacy and low side effects for the informed or an improvement of sexual performance or an increase of muscle strength for the sex-oriented narcissist, but it does not mean that all of them would be willing to use the method even if all these requirements were fulfilled.
Differences in their geographical distribution and socioeconomic factors and most importantly in the factors and attributes that influence the likelihood of using or not using the new MFC are noticeable and will allow developing different concepts for marketing.
The informed group is interested in his own safe and easy-to-use contraception, but also very concerned about potential risks and side effects as well as about a potentially low efficacy of an MFC method. Members of this group need comprehensive background information regarding the mode of action, the efficacy, and certainly about reversibility. They also want information concerning potential side effects of any kind. If this information is not provided this would influence their willingness to use such an MFC.
The average educational level in this group is higher compared with the 2 other groups. That might be the reason for the increased interest in more specific background information and might also lead to a better understanding of the provided facts and data. The higher educational level will probably also influence the taste regarding which newspapers and journals are read. The Internet plays a more important role for the informed group than for the 2 other groups. One could speculate that the informed group is more willing to actively look for detailed information. If only superficial information is published, for instance, in the yellow press, and the informed group becomes interested in this kind of method, he will look for other information sources like reputable journals or the Internet. A specific homepage on the Internet could offer the opportunity to find information about the efficacy, study results regarding side effects, and background information about the mode of action and to ask questions to specialists.
The informed group considers the physician, the pharmacist, and journals to be more important information sources than the Internet. The 2 first are specialists, and asking questions and getting immediate answers is possible. Articles in journals, especially if well investigated, give a good overlook about the topic and also concentrate on negative side effects. But with this preference the informed group does not differ much from the 2 other groups.
The average income level of the informed group is higher than the 2 other groups. If the primary parameters of the new method are satisfactory for the informed man, he might be more willing to pay a premium price even if additional positive effects of the testosterone are not stressed—although, for him, these additional effects would probably also lead to a higher acceptance.
The informed group is very important in Europe, especially in Germany and Sweden, where it forms the main group compared with the 2 other groups. In Argentina—in contrast to the 2 other Latin American countries—the informed group is also the most important user group, even more important than in Spain and France. In the United States, Mexico, and Brazil the informed group belongs to the less important groups; in Indonesia this group is almost nonexistent.
The sex-oriented narcissist is mainly interested in a positive effect on his sexual life (enhancement of libido, sexual performance, and satisfaction). And to the same extent he is concerned that this method might interfere with or even threaten his sex life. Additionally his choice would be influenced if the new method had a positive impact on his body such as an increase of muscle strength or a positive influence on body frame. If these positive side effects can be proven and are promoted, that will definitely bring an increase in acceptance for the new contraception method in all 3 clusters, but for this group these attributes are the main concern.
On the other hand, this group is also characterized by a disapproving attitude toward male fertility methods and new drugs. It probably would be hard to convince members of this group to use the new method even if it had promising primary attributes (such as a very good efficacy), so the secondary positive side effects become decisive in the decision-making process.
Although the income level is lower in this group compared with the informed group, the potential user might be willing to pay a good price for that kind of fertility control if he can expect something more than just an effective fertility control. The sex-oriented narcissist does care less about contraception in general compared with the informed group.
The sex-oriented narcissist is the most important user group in the United States, Mexico, and most imposing in Brazil.
The religious refuser has a rather negative attitude toward any drug and any male fertility control method. Religious reasons play a main role for the disapproval. As explained before, the composition of the 3 clusters is by no means absolute. The religious refuser group also contains men who do not have a special religious reason to reject the method but were included here due to other factors that are important to them and that fit best in this cluster. Even though this group shows a smaller willingness to use the new method, that does not mean that (for instance) a sex life improving character of the method would not positively influence them to use the new MFC method.
In Indonesia he forms the main group; in the United States, Mexico, and Brazil he also plays a very important role. He is rather unimportant in the other participating countries.
The religious refuser has the lowest average educational and income level of all 3 groups and also the lowest current use of any contraception method. One can speculate that marketing campaigns promoting the contraceptive effects and providing comprehensive information about primary method attributes would not really touch him.
Physicians and journals would also be the preferred information sources for the religious refuser, but he would rather ask friends than a pharmacist to get further information; and the Internet is the least accepted information source for him.
Conclusion
The results based on collected data in the MFC study support the view that
there is a market for MFC methods. However, market segmentation should be
further considered before launching this method. In addition, further studies
should follow closer to the launching date (ie, once a method can be more
precisely characterized).
One very important issue that still has to be considered is the role of the female partner in the decision-making process. The vast majority of male respondents stated that they would decide about the contraception method together with their partners—and if only 1 partner decides, it is more frequently the woman. Strong influence by women will make it necessary to learn more about their attitudes toward such new methods as well. Therefore studies among women should definitely be included in the future planning of acceptance surveys.
Footnotes
Parts of this work are closely associated with the theses of Martin
Wiesemes and Klaas Heinemann. 
This study was supported by an unrestricted grant from the Schering AG.
The authors (F.S. and M.W.) are employees of the Schering AG, which is developing a male fertility control method. There seems to be no conflict of interest as far as the results of this survey are concerned.
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