Research and discussion paper:

A descriptive study of sexual dysfunction and gender identity clinic in the University of Hong Kong Psychiatric Unit, 1991 – 2001

JOHN SIK-NIN KO, Department of Psychiatry, University of Hong Kong, Queen Mary Hospital, Hong Kong

(Extracts from a dissertation submitted as part of the Part III Fellowship Examination for the Hong Kong College of Psychiatrists, posted on this website 24/3/03 with the kind permission of the author)

 

LIST OF ABBREVIATIONS

DSH Deliberate self harm

DSM-IV Diagnostic and Statistical Manual 4th edition

F Female

F to M Female-to-male

ICD-10 International Classification of Diseases 10th revision

M Male

M to F Male-to-female

Sex Clinic The specialized sex clinic in Queen Mary hospital

SRS Sex reassignment surgery

TS Transsexual

TV Transvestite

 

SPECIAL SYMBOL

>< material here skipped which is in the original dissertation

ABSTRACT

This study aimed to examine all the patients seen in the Sex Clinic of the Hong Kong University Psychiatric Unit from 1991-2001 by studying retrospectively their case records. A total of 376 cases were identified. Three hundred and forty-two of them were referred for assessment relating to sexual dysfunction. >< Thirty-four cases were referred for assessment relating to sex reassignment surgery. Twenty-eight were found to fulfil the DSM-IV diagnostic criteria for transsexual. They were usually in their late 20s with at least secondary education, full time employment (71.4%), never married (89.2%) and sexually inactive (64.3%). Their onset of gender dysphoria was usually before age 13 (82.1%) and most of them had cross dressing behavior (92.9%). Among them were 13 male-to-female transsexuals and 15 female-to-male transsexuals, giving a M:F ratio of 1:1.15. The male-to-female transsexual might have a trend of being more highly educated and more likely to take hormonal therapy. Some male-to-female transsexuals were once married in their anatomical sex (17.9%) and some were bisexual (10.7%) or heterosexual (3.6%). All the female-to-male transsexuals were homosexual in orientation and none were ever married in their anatomical sex. In summary >< the demand for assessment for sex reassignment surgery was low compared with some European and Asian countries. Slight predominance of female-to-male transsexuals were found and they were found to be different from the male-to-female transsexuals in certain aspects.

1 INTRODUCTION

><

1.3 Hong Kong Sex Clinic in the 80’s

In 1981 the first documented case of sex reassignment surgery (SRS) for a transsexual patient was performed in Hong Kong. In 1986 a Gender Identity Team (Ng et al 1989), comprised of psychiatrist, clinical psychologist, gynecologist, endocrinologist, urologist, medical social worker (Chong 1990, Chong 1991, Ma 1999) and lawyer, was established in the Sex Clinic. The team was modeled after that of the Clark Institute of Psychiatry in Toronto, Canada and aimed to provide assessment and counseling service to transsexuals in Hong Kong. The clinic is now still the only center providing such service in the whole of Hong Kong.

1.4 Hong Kong Sex Clinic in the 90’s

Starting from 1991, psychiatry trainees were involved in the management of all kind of cases seen in the clinic, under the supervision of a consultant psychiatrist. Due to the limited resources, there was only one non-private clinic session per week and only one new case could be assessed every week. With the increase in the demand for high quality service, a private sex clinic manned by a senior psychiatrist was also launched in 1995.

><

1.8 Aims of this study

The present study is a retrospective study of all patients seen in our specialized Sex Clinic in the University of Hong Kong Psychiatric Unit at Queen Mary Hospital over a eleven-year period from January 1991 to December 2001. It was carried out with the following aims:

><

( 2 ) For patients referred for sex reassignment surgery

                   2a. to describe the demographic characteristics of transsexuals

                   2b. to describe the clinical profile of transsexuals.

2c. to compare the male to female with the female to male transsexuals with reference to demographic and clinical profile.

2. METHOD

2.1 Design

The present study would retrospectively review the clinical information of the Sex Clinic between 1 January 1991 to 31 December 2001 by studying the clinical notes of the patient records. The period was chosen because the record before 1991 was already destroyed. 1991 was also the year when psychiatric trainees were involved in patient management in the Sex Clinic. The candidate (SNK), being a senior psychiatric trainee, was directly involved in management of all non-private clinic patients in the year 2000 and 2001. The private clinic patients were managed by a consultant psychiatrist specialized in sexology.

2.2. Subjects

ll patients first seen in the sex clinic between 1 January 1991 to 31 December 2001 were included. Computer registry was used to trace the new patients in the period between 1 January 2000 and 31 December 2001 as the registry was computerized since 1 January 2000. Manual registry recorded in a registration book was used to identify the patient records before 1 January 2000. All patients would have their personal particulars written down in the registration book when they first attended the Sex Clinic. All the remaining records kept in the outpatient department were again checked through to make sure that there were no missed files. Every effort has been made to avoid omitting any records. The above was carried out by the candidate (SNK) with the help of a research assistant. Three hundred and seventy-six records were identified. Three hundred and forty-two patients were referred for assessment relating to sexual dysfunction and 34 patients were referred for assessment of suitability for sex reassignment surgery.

><

2.3 Data collection for patients referred for assessment related to sex reassignment surgery

The case notes of patients referred for assessment for sex reassignment surgery was studied in detail. The required information was entered into a data sheet specially designed for this group of patients. Data entry was completed and was double-checked by the candidate (SNK) before subjecting to statistical analysis. The diagnosis of transsexual was made according to DSM-IV.

Socio-demographic data including presenting age, presenting sex, education level, employment status, job categories and marital status were collected. The presenting age was the age when the patient was first seen in the Sex Clinic. Presenting sex referred to the gender when they first presented to the Sex Clinic, which was the same as their anatomical sex at birth. A person presenting as male would be a male-to-female transsexual while a person presenting as female would be a female-to-male transsexual.

Clinical profile data including the following was collected. Referrer was recorded down according to the referral letter. Onset age was divided into two groups. One with onset before age 13 and one at or after age 13, dividing the onset into pre and post-pubertal (Burns et al 1990). Cross-dressing would be counted as present if they did this for at least once a month. Real-life test, sometimes called real-life experience (Levine et al 1998), meant that they would function in the new gender before the surgery. The new gender roles might include full or part-time employment, being a student, participating in community-based volunteer activity and with the knowledge of other people, besides their therapist. Regarding sexual orientation, we preferred to classify them as either attracted to male, to female, or to both. So if a male-to-female transsexual was attracted to a male, they were considered homosexual in orientation. If they were attracted to a female, they were considered as heterosexual. And if they were attracted to both, they were considered as bisexual. Sexually active meant that they have sex play with partners, male or female or both, or with themselves at least once every two months, and the activity did not have to be penetrative. Concurrent co-morbid psychiatric diagnosis was made according to DSM-IV. History of DSH included all form of deliberate self-harm behavior, for at least once in their lifetime. SRS meant whether one had completed the sex reassignment surgery or not. Hormonal treatment included those prescribed by doctors or self purchased.

2.4 Statistical analysis

Data collected was analyzed using the Statistical package for the Social Sciences (SPSS version 11). Mean and range were used to summarize the continuous variables and t-test was used to analyze between group differences. Categorical variables were summarized by percentage. Pearson Chi-square test was used for correlation analysis. In view of the small sample size in subgroup analysis, categories were combined and Fisher exact test (Cochran 1952) was used when the number in the cells was small. The significant level was set at p<0.0034 (two tailed). To adjust for the multiple comparison (14 in total), significance at the trend level was set at 0.0034 ≤ p < 0.05.

3 RESULTS

><

3.6 Transsexuals

Thirty-four subjects were referred for assessment for sex reassignment surgery (SRS). Six did not fulfil the DSM-IV diagnostic criteria of transsexual. These six subjects were all presenting as male. Their mean age was 36 (range 18-54). Five were dual role transvestites and one was an effeminate homosexual. They were assessed for suitability of sex reassignment surgery and were all found to be unsuitable.

3.7 Socio-demographic profile of transsexuals

The remaining 28 subjects were diagnosed as transsexual according to DSM-IV. They consisted of 15 females and 13 males when presenting. They were predominantly young adult (mean age = 29.1 range 19-42) when presenting, finished their secondary education (71.4%), never married (89.2%), employed full time (71.4%), and working as an executive (64.3%). A summary of demographic data was illustrated in Table 8.

 

 

Table 8: Demographic summary of transsexuals (n = 28)

Presenting Age

Mean (range)

29.1 (19-42)

Presenting sex

Male

N (%)

13 (46.4)

Female

15 (53.6)

Education

Primary

N (%)

0 (0.0)

Secondary

20 (71.4)

Tertiary

8 (28.6)

Employment

Unemployed

N (%)

5 (17.9)

Status

Part-time

1 (3.6)

Full-time

20 (71.4)

Retired

0 (0.0)

Student

2 (7.1)

Job Categories

Executive

N (%)

20 (71.4)

Skilled professional

3 (10.7)

Non skilled

0(0.0)

Unemployed

5 (17.9)

Marital status

Single

N (%)

23 (82.1)

Married

1 (3.7)

Cohabited

2 (7.1)

Divorced

2 (7.1)

3.8 Clinical profile of transsexuals

As the only assessment center for transsexuals, there were referrals from other psychiatrists (42.9%), from family doctors (28.6%), from other specialties (10.7%) such as urologists and gynecologists and from clinical psychologists and counselors (17.9%). The majority had pre-pubertal onset before age 13 (82.1%). An even larger majority had cross dressing behavior (92.9%) and more than two thirds (71.4%) had real-life test for at least two years. About half of them (57.2%) were sexually attracted to females and about two thirds (64.3%) were sexually inactive. About one third (32.1%) had co-morbid psychiatric disorders and a quarter (25%) of them had history of deliberate self-harm (DSH). Hormonal treatment was taken in less than half of the subjects (42.9%). Only half of them (50%) had completed sex reassignment surgery (SRS). Half of them (50.0%) were attending follow-up. Among those were 7 who still had not undergone SRS and were being reassessed. Of the 14 (50%) not attending follow-up, half of them (25%) had completed SRS. Table 9 summarized their clinical profile.

 

Table 9: Clinical profile of transsexuals (n = 28)

Referrer

Psychiatrist

N (%)

12 (42.9)

Family doctor

8 (28.6)

Specialist doctor

3 (10.7)

Counselor

5 (17.9)

Onset age

< 13

N (%)

23 (82.1)

³ 13

5 (17.9)

Hormone

Yes

N (%)

12 (42.9)

Treatment

No

16 (57.1)

Cross-dress

Yes

N (%)

26 (92.9)

No

2 (7.1)

Real-life test

< 2 years

N (%)

8 (28.6)

³ 2 years

20 (71.4)

Sexual orientation

Attracted to M

N (%)

9 (32.1)

F

16 (57.2)

Both

3 (10.7)

Sexual activity

Active

N (%)

10 (35.7)

Inactive

18 (64.3)

Psychiatric

No

N (%)

19 (67.9)

Diagnosis

Depression

8 (28.5)

Psychosis

1 (3.6)

History of DSH

Yes

N (%)

7 (25.0)

No

21 (75.0)

SRS

Yes

N (%)

14 (50.0)

No

14 (50.0)

Follow-up

Regular

N (%)

11 (39.3)

Irregular

3 (10.7)

No

14 (50.0)

3.9 Comparison between male-to-female and female-to-male transsexuals

There seemed to be a trend of male-to-female transsexuals receiving more tertiary education (c 2 = 7.60, p = 0.011). Three male-to-female transsexuals were married in their anatomical sex. No female-to-male transsexual was ever married or divorced. The sexual orientation was different (c 2 = 24.23, p = < 0.001) between the two groups. All female-to-male transsexuals were attracted to females. Three male-to-female transsexuals were attracted to both and one was attracted to female. There seemed to be a trend of more male-to-female transsexuals taking hormonal treatment than female-to-male transsexuals (c 2 = 6.892, p = 0.020). Other parameters were not found to be significantly different. A summary of the above findings was illustrated in Table 10.

 

Table 10: Difference between M-to-F and F-to-M transsexuals (n = 28)

M-to-F

F-to-M

Statistics

Presenting age

Mean (s.d.)

31.5 (7.8)

27.1 (5.7)

T = 1.75

       

P =0.092

         

Referrer

Psychiatrist

7

5

c 2 = 1.20

 

Non-psychiatrist

6

10

P = 0.2746

         

Education

Secondary

6

14

c 2 = 7.60

 

Tertiary

7

1

P = 0.011

         

Marital status

Never married

10

15

c 2 = 0.049

 

Married/ divorced

3

0

P = 0.087

         

Onset

< 13

10

13

c 2 = 0.45

 

³ 13

3

2

P = 0.639

         

Cross-dress

Yes

13

13

c 2 = 1.867

 

No

0

2

P = 0.484

         

Real life test

< 2 years

4

4

c 2 = 0.06

 

³ 2 years

9

11

P = 1.000

         

Sexual

Attracted to M

9

0

c 2 = 21.09

Orientation*

F

1

15

P = < 0.001

         

Sexual

Active

7

3

c 2 = 3.48

activity

Inactive

6

12

P = 0.114

         

Psychiatric

None

9

10

c 2 = 0.02

Diagnosis

Yes

4

5

P = 1.000

         

History of DSH

Yes

2

5

c 2 = 1.197

 

No

11

10

P = 0.396

         

Hormone

Yes

9

3

c 2 = 6.892

Treatment

No

4

12

P = 0.020

         

SRS

Yes

6

8

c 2 = 0.144

 

No

7

7

P = 1.00

         

Follow-up

Yes

8

6

c 2 = 1.29

 

No

5

9

P = 0.256

         

* the group attracted to both (n = 3) were excluded for analysis

4 DISCUSSION

><

4.5 Low demand for assessment regarding sex reassignment surgery in Hong Kong

Given that the Sex Clinic was the only gender identity disorder assessment center in the whole of Hong Kong (approximately 7,000,000 population), the number of referral for assessment regarding sex reassignment surgery was found to be low. In Netherlands the prevalence of male-to-female transsexual was estimated to be 1:45,000 and for female-to-male transsexual was 1:200,000 in 1980. In 1986 the figure was revised to 1:18000 for male-to-female and 1:54000 for female-to-male (Eklund et al 1988). The increased prevalence was suggested to be due to a lower threshold for applying for medical treatment rather than to a true increase in the prevalence. The incidence figures were found to be constant over time in Sweden (Landen et al 1996b). The prevalence of transsexual in Singapore was estimated to be 1:25000 for male-to-female (Tsoi et al 1977) and 1:36000 for female-to-male (Tsoi et al 1980). This figure was again revised up to 35.2 per 100,000 population age 15 and above (or 1/2900) for male-to-female and 12.0 per 100,000 (or 1/8300) for female-to-male transsexual (Tsoi 1988). In Taiwan, the figure in 1988 was 97 per 100,000 population aged 18 or above (or 1/1030) for all transsexuals (Hwu et al 1989). No prevalence figure was available from mainland China.

There might be several reasons. We might have a really low prevalence of transsexual, below other countries including, Taiwan, Singapore, and Netherlands. There was no evidence that Chinese culture dislike transsexual. Trans-gender roles were often played out on stage and enjoyed by the audience (Tan 2000). There might be a high threshold for applying for medical treatment. The service of the Sex clinic, being the only center assessing and making arrangement for all transsexuals in Hong Kong, might not be known to them or might not be user friendly enough. The real-life test might be too difficult in this community especially for male-to-female transsexual. Patients seen by the candidate (SNK) reported much difficulty in finding employment or study or charity work under the assumption of their new gender, until after the operation. Their real-life test or experience might usually consist of assuming their new gender after work or when going out at night and on holiday. This was also probably reflected in the one quarter (25 %) of transsexuals who stopped attending follow-up during the assessment period, before they could have SRS. The transsexual in Hong Kong might have SRS done by private doctors or in neighboring countries. In nearby Thailand, they could have SRS done within one month including pre-operation assessment. It would cost a person about fifty thousand Hong Kong dollars (equivalent to four thousand British pounds) for the whole package.

4.6 Slight predominance of female to male transsexual in Hong Kong

The M:F ratio in Singapore was found to be 3 to 1 (Tsoi 1988), similar to that of Netherlands (Eklund 1988), of United Kingdom (Burns et al 1990) and in Sweden (Landen et al 1996) In Germany the ratio in 1970-1994 was found to be 2 to1 (Garrels et al 2000) predominated by men. But in the following 4 years the ratio altered considerably to 1.2 to 1. The drop in the sex ratio was explained either as a reduction of an overhang of male-to-female transsexuals. Or as an artificial phenomenon caused by recent developments in therapy and by the views of transsexuals' groups on the treatment they were offered. The figure in Taiwan (Hwu et al 1989) showed a reverse predominance of 14.62 to 1 in favor of female. Our study showed a 1.15 to 1 in favor of female. This was similar to a ratio of M:F of 1 to 1.22 in China (Fang 1994). The reason for the difference is unknown. We might postulate some cultural factor in Chinese. There was a theme of ‘son-preference’ in traditional Chinese thinking, Men were valued more than women. In China where there was a policy of one child family, there were incidents of sex-selective abortions, neglect, or even infanticide. Therefore changing from a female to a male might bring higher social status. Psycho-dynamically they might be fulfilling the wish of their parents.

4.7 Difference between male-to-female and female-to-male transsexuals

We found that our male-to-female transsexual seemed to have a trend of being more highly educated. In Netherlands, they found that the female-to-male transsexuals were more often employed or enrolled in a study (Verschoor & Poortinga 1988). This was different from Singapore findings (Tsoi 1992) as many of their male-to-female transsexuals were less educated and employed as prostitutes. In the States, they found that twice as many male-to-female transsexuals were unemployed and receiving welfare at the time of application (Dixen et al 1984). They were also found to have more acting-out behavior such as criminal convictions and involvement in prostitution. Regarding history of deliberate self-harm there was no significant difference between the male-to-female and female-to-male transsexuals. We must take note that our series had a lower DSH rate (25%) compared with 39% found in Maudsley series (Burns et al 1990) and 85% in the China series (Fang 1994).

None of the female-to-male transsexuals was ever married in their anatomical sex and two of them lived in a stable relationship with a partner of their own biological sex. This was similar to the Dutch (Verschoor & Poortinga 1988) and German (Kockott & Fahrner 1988) findings. Three of our male-to-female transsexuals were married in their anatomical sex of which two had divorced. This was similar to study in Sweden (Landen et al 1998).

All of the female-to-male transsexuals were attracted to female, that is, they were homosexual in orientation. Heterosexuality was more prevalent in male-to-female transsexual (Burns et al 1990, Dixen et al 1984, Sorensen & Hertoft 1982, Landen et al 1998). Bisexuality occurred exclusively in male-to-female transsexuals and was confirmed by UK findings (Burn et al 1990).

The male-to-female transsexuals seemed to have a trend of using more hormonal treatment. Similar data was found in the States (Dixen et al 1984). This might point to the significant bodily changes of the female hormones on male. It might also be due to the fact that female-to-male transsexuals accepted a less masculine appearance, emphasized less on their sex appeal and more on their gender roles. This was suggested by the findings that they were less sexually active than the male-to-female transsexuals.

Out of the 34 subjects referred for sex reassignment surgery, six did not fulfil the diagnostic criteria of DSM-IV as a transsexual. They were all presenting as male. Five of them were dual role transvestites. That is to say, they liked to cross dress in order to experience temporarily membership of the opposite sex. They might not have any sexual motivation for the cross dressing and they did not have the desire for a permanent change to the opposite sex. All the above findings suggested that the male subjects referred for sex reassignment surgery consisted of a more heterogenous group of people than female-to-male transsexuals.

5 LIMITATIONS

The design of this study had several limitations. This study described and reviewed the service data of the Sex Clinic of Queen Mary Hospital of University of Hong Kong in the period 1991 to 2001. Over a period of 11 years, the sample studied represents all the cases treated in the sex clinic between 1991-2001. The results, including the pattern of sexual dysfunction and the outcome, could only represent the experience at Queen Mary Hospital and might not represent the problems of Hong Kong as a whole. However this was still a significant sample. It could reflect the magnitude of the problems, as there was no other sex clinic in Hong Kong before 1997. Some patients were treated by private doctors, and this would apply to all other studies of a similar nature. The sample might however bias to a group of patients with more psychopathology or severity. This was unavoidable from clinic samples. Future multi-center studies and trials, as suggested by Gregoire and Bhugra (1996), may offer more satisfactory alternatives.

The data of this study was based on records retrieved both by computer (system was only in use for 2 years) and manual registry. Every effort has been made to be as thorough as possible but over such a long period of time some of the records would have been misplaced or missing. This was unfortunately unavoidable and the missing data would be conservatively estimated to be less than 10%. Very likely the bias thus created would be random and non-systematic and would not affect the result of this study to a very large extent.

A general limitation of all retrospective case record studies is non-standardized data collection. Different psychiatry trainees assessed subjects at various times throughout the study period. No standardized record format or assessment scale was used. Treatment modality and method were also not standardized. The therapy method utilized was not usually fully described. Nevertheless we had the fortune of having the same supervisor during the whole period of eleven years. Future prospective study with standardized assessment instruments, treatment protocols, randomization, and controls (for example waiting list, no treatment or placebo treatment) would improve the robustness of the results.

There was no systematic follow-up tracing and monitoring programme for the subjects. The progress of the dropout was unknown. No conclusion or inference could be made on what percentage of cured subjects had recurrence of their disorders. In case of the transsexual cases, no conclusion could be drawn on the long-term beneficial effect of sex reassignment surgery as compared to those who chose not to undergo surgery. Further longitudinal study is required.

><

6 CONCLUSIONS

Compared to some countries in Europe and Asia, we have a lower demand for assessment related to sex reassignment surgery. The transsexuals assessed were more likely to be single, full-time employed and sexually inactive. They usually had their onset of gender dysphoria before age 13 and most had cross dressing behavior. The M:F ratio of our transsexuals assessed was 1:1.15 with female predominance. The male-to-female transsexuals might be better educated and more likely to use hormonal treatment. The female-to-male transsexuals were all found to be attracted to female (homosexual in orientation), which was different from male-to-female transsexuals. No female-to-male transsexual had ever been married in her anatomical sex and bisexuality was exclusively found in male-to-female transsexuals. The gender identity assessment function of the Sex Clinic may be more widely publicized in Hong Kong so that more people in need may know. Some system of following up the patients who stopped attending follow-up may shed light on the outcome of sex reassignment surgery, the post-operative psychological and social adjustment and ways of improving our service. ><

 

REFERENCES

 

Burns, A., Farrell, M. & Brown, J. C. (1990) Clinical Features of Patients Attending a Gender-Identity Clinic. British Journal of Psychiatry, 157, pp. 265- 268.

Chong, J. (1990) Social Assessment of Transsexuals Who Apply for Sex Reassignment Therapy. Social Work in Health Care, Vol. 14 (3), pp. 87-105.

Chong, J. (1991) Transsexualism- A Challenge to Social Work Practice. The Hong Kong Journal of Social Work, Vol. 23, pp.2-9.

Cochran, W.G. (1952) The c 2 test of goodness of fit. Annals of Mathematics. 23, pp315-345.

Dixen, J.M., Maddever, H., Van Maasdam, J. & Edwards, P.W. (1984) Psychosocial characteristics of applicants evaluated for surgical gender reassignment. Archives of Sexual Behavior. 13 (3) pp 269-276.

Eklund, P.L., Gooren, L.J. & Bezemer, P.D. (1988) Prevalence of transsexualism in the Netherlands. British Journal of Psychiatry, 152, pp 638-640.

Fang, M.I. (1994) Clinical analysis of 40 cases with transsexualism. Chinese Journal of Psychiatry, 12 pp 160-167.

Garrels, L. Kockott G., Michael, N., Preuss, W., Renter, K., Schmidt, G., Sigusch, V. & Windgassen, K. (2000) Sex ratio of transsexuals in Germany: the development over three decades. Acta Psychiatrica Scandinavia 102 (6) pp 445-448.

Gregoire, A. & Bhugra, D. (1996) Outcome studies of psychological interventions: lessons,from sex therapy research. Sexual and Marital Therapy, Vol. 11, No. 4, pp. 407- 418.

Hwu, H.G., Yeh, E.K. & Chang, L.Y. (1989) Prevalence of psychiatric disorders in Taiwan defined by the Chinese Diagnostic Interview Schedule. Acta Psychiatrica Scandinavia, 79 (2), pp 136-147.

Kockott, G. & Fahrner, E.M. (1988) Male-to-female and female-to-male transsexuals: a comparison, Archive of Sexual behaviour 17 (6) pp 539-546.

Landen, M., Walinder, J. & Lundstrom, B. (1996b) Incidence and sex ratio of transsexualism in sweden, Acta psychiatrica Scandinavia, 93 (4), pp 261-263.

Landen, M., Walinder, J. & Lundstrom, B. (1998) Clinical Characteristics of a total cohort of female and male applicants for sex reassignment: a descriptive study. Acta psychiatrica Scandinavia 97 (3) pp 189-194.

Levine, S.B., Brown, G., Coleman, E., Ceohen-Kettenis, P., Hage, J.J., Van Maasdam, J., Petersen, M., Pfaefflin, F. & Schaefer, L.C. (1998) The standards of care for gender identity disorders. The International Journal of Transgenderism Vol 2, No.2

Ma, J.L.C. (1999) Social work practice with transsexuals in Hong Kong who apply for sex reassignment surgery, Social Work in Health Care, vol 29 (2), pp 85-102.

Ng, M.L., Wong, K.K., Chow, S.K, Tang, G.W.K., Leung, A. & Chan, M.M. (1989) Transsexualism: Service and Problems in     Hong Kong. Hong Kong Practitioner 11(12), pp. 591-602.

Sorensen, T. & Hertoft, P. (1982) Male and female transsexualism: the Danish experience with 37 patients. Archives of Sexual Behavior, 11 (2) pp 133-155.

Tsoi, W.F. (1988) The prevalence of transsexualism in Singapore. Acta Psychiatrica Scandinavia, 78 (4) pp 501-504.

Tsoi, W.F. (1992) Male and female transsexuals: a comparison. Singapore Medical Journal. Apr; 33 (2) pp 182-185.

Tsoi, W.F. & Kok, L.P. (1980) Female transsexualism in Singapore: a report on 20 cases.Australian and New Zealand Journal of psychiatry 14 (2), pp 141-143.

Tsoi, W.F., Kok, L.P. & Long, F.Y. (1977) Male transsexualism in Singapore: a description of 56 cases, British Journal of Psychiatry, 131, pp. 405-409.

Verschoor, A.M. & Poortinga, J. (1988) Psychosocial differences between Dutch male and female trannsexuals. Archive of Sexual Behavior, 17 (2) pp 173-178.

Home