Preliminary results are preliminary, not "unfounded": reply to Morris and Waskett.
|Article Type:||Letter to the editor|
Impotence (Risk factors)
Circumcision (Complications and side effects)
Van Howe, Robert
|Publication:||Name: International Journal of Men's Health Publisher: Men's Studies Press Audience: Academic; Professional Format: Magazine/Journal Subject: Health Copyright: COPYRIGHT 2012 Men's Studies Press ISSN: 1532-6306|
|Issue:||Date: Summer, 2012 Source Volume: 11 Source Issue: 2|
|Geographic:||Geographic Scope: United States Geographic Code: 1USA United States|
We appreciate the interest that our preliminary study has generated
and would like to respond to comments made in the critique by Morris and
We acknowledged the limitations of our study, primarily the potential for selection bias, in the original publication. All research begins with an idea that becomes a hypothesis. The first step is to see if others have tested the hypothesis. If no one else has, the hypothesis is usually tested using a convenience sample. Convenience samples are used because of limited resources and access to a representative sample is limited and expensive. If the data from the convenience sample supports the hypothesis, then it needs to be confirmed with a more representative sample. This is where our line of inquiry stands. We have made no claims beyond our preliminary findings. Our findings are unconfirmed, not "unfounded." To be "unfounded" there would need to be a study of a representative sample with sufficient power to show our findings were errant. Such a study has not been done.
An example of how the research process works is exemplified by research on the impact of male circumcision on the sexual experience of the female partner. A study of a convenience sample found that the male partner's circumcision status had a significant impact on a woman's sexual pleasure (O'Hara & O'Hara, 1999). Recently, a national health survey confirmed these findings, noting that compared to women with normal male partners, women with circumcised male sexual partners were significantly more likely to report "incomplete sexual needs fulfillment" (adjusted OR = 2.09, 95% CI = 1.05 - 4.16), overall sexual function difficulties (adjusted OR = 3.26, 95% CI = 1.15 - 9.27) (including orgasm difficulties: adjusted OR = 2.66, 95% CI = 1.07 - 6.66), and dyspareunia (adjusted OR = 8.45: 95% CI = 3.01 - 23.74) (Frisch, Lindholm, & Gronbaek, 2011).
Many of the claims made by Morris and Waskett are unfounded. For example, to suggest that we "have actively encouraged such bias" is untrue, unprofessional and unsubstantiated. Our data showed that circumcised men were more likely to report erectile dysfunction (age adjusted OR = 1.87, 0.69 - 5.05). While our findings are not statistically significant, this does not mean there is "no difference in erectile dysfunction (ED) between circumcised and uncircumcised men." We found an increased likelihood of a difference that should be explored further and which is consistent with the results of a national survey in which circumcised men reported significantly more orgasm difficulties (adjusted OR = 3.26; 95% CI = 1.42 - 7.47) than normal men (Frisch, Lindholm, & Gronbaek, 2011). And, a late-breaking article found that circumcised men were four times as likely to fail to achieve a normal erection from penilo-carvenosum reflex elicitation than circumcised men (p < .001) (Podnar, 2012). Also, Morris and Waskett should be aware that one cannot prove the null hypothesis.
In addition to impacting orgasms, circumcision has been linked in several studies to premature ejaculation, with circumcised men having nearly five times the rates of normal men, suggesting that there may be trauma from circumcision (Kim & Pang, 2007; O'Hara, & O'Hara, 1999; Richardson & Goldmeier, 2005; Tang & Khoo, 2011). Studies from the Karolinska Institute in Sweden (and elsewhere) have shown that perinatal events have a long-term impact on behavior (Anand, Runeson, & Jacobson, 2004; Jacobson & Bygdeman,1998: Jacobson, Eklund, Hamberger, Linnarsson, Sedvall, & Valverius, 1987: Jacobson, Nyberg, Eklund, Bygdeman, & Rydberg, 1988; Jacobson, Nyberg, Gronbladh, Eklund, Bygdeman, & Rydberg, 1990; Nyberg, Allebeck, Eklund, & Jacobson, 1992, 1993; Zornberg, Buka, & Tsuang, 2000). These events, based on increases in cortisol levels, are less stressful than infant circumcision, so one would expect that circumcision is also likely to have long-term impact on behavior. It has also been shown that circumcised boys cry longer and louder than normal boys when vaccinated at four to six months of age (Taddio, Goldbach, Ipp, Stevens, & Koren, 1995; Taddio, Katz, Ilersich, & Koren, 1997). The long-term effects of "circumcision trauma" are accepted by all but a small minority.
The words "Low, Moderate, and High" were inadvertently inserted into the legend of our Figure. We apologize for any confusion this may have caused. It is unclear how this typographical error was "unmathematical," as the figure speaks for itself.
We were surprised by Morris and Waskett's use of the "cut and weigh" to determine the area under the curve as a possible replacement for two-by-two tables in evaluating dichotomous and categorical variables. Typically, dichotomous variables are evaluated by calculating a chi-square, a Fisher's exact test, or a Mantel-Haenszel (MH) odds ratio, thus eliminating need for a scissors or a scale. When the respondents were categorized as having low, moderate or high ALEX scores, a statistically significant trend for circumcised men to have higher scores (chi-square (df = 1) = 6.11,p = .0134) was found. Of the circumcised men who responded to the survey 78 of 236 (33.1%, 95% CI = 27.05 - 39.05) had a low ALEX score. Of the normal men, 34 of 64 (53.1%, 95% CI = 40.9 - 65.35) had a low ALEX score. The chi-square for the two-by-two table was 8.67, which corresponds to a p-value of .0032. The Fisher's exact p-value was .0053. The MH odds ratio was 2.30 (95% CI = 1.31 - 4.02). All of these differences are statistically significant, even when adjusted for multiple comparisons using the Bonferroni method. Of the circumcised men 94 of 236 (39.8%, 95% CI = 33.6 - 46.1) reported a high ALEX score while 19 of 64 (29.7%, 95% CI = 18.5 - 33.5) of normal men reported a high ALEX score (OR = 1.56, 95% CI = 0.86 - 2.85). When the number of men with high ALEX scores are compared to the number men with low ALEX scores, circumcised men were significantly more likely to have a high ALEX score (OR = 126.96.36.199 - 4.08).
We were further surprised by the comments that "an n value of 23 is too low to provide confidence that the conclusion reached is reliable." We are unsure of where this notion came from. We speculate that Morris and Waskett are referring to the number of patients needed to satisfy asymptotic assumptions. For example, if a cell of a two-by-two table or a stratum has a count of ten or fewer (some say five or fewer) the asymptotic assumptions that allow for the calculation of accurate estimates using common statistical methods are not met. In such cases calculations using exact statistics are needed to provide accurate results. For example, a study with data from five countries was published in the New England Journal of Medicine in which seven of the 20 cells (four cells for each of five countries) had a count of five or fewer, yet exact statistics were not used. Consequently, their estimates were calculated using unreliable statistical methods, so the reported results are likely to be inaccurate (Castellsague et al., 2002). The only two-by-two table in our report that had a cell with a count fewer than five was in the comparison of the number of men who had taken medication for erectile dysfunction. When tested using Fisher's exact test, the p-value was .0058.
Morris and Waskett note that in general populations only 10 percent will have high ALEX scores, and the high rates seen in our study suggests that our population is unrepresentative. By this standard the rates for high ALEX scores were high in both our circumcised men and our normal men. The fact that the overall rates of high ALEX scores in the population we studied are higher than expected in the population at large does not mean that difference seen between circumcised and normal men is not valid. It indicates that a difference exists in a population with a higher than average rate of high ALEX scores. As we noted in our original publication we believe these findings need to be replicated in other populations.
It seems that our statement "Circumcision pain itself did not seem to effect [sic!] acquiring alexithymia" is taken out of context. It appears that circumcision, regardless of whether anesthetics were used, affects alexithymia scores.
The use of erectile dysfunction medication is more likely to be a measure of the severity of erectile dysfunction than a measure of economic access to the medication. We believe that Morris and Waskett wrongly assert that circumcision is consistently associated with upper socioeconomic indices. This association has shifted with time. More recent studies have found that mothers who do not have their sons circumcised are more likely to have greater levels of education. As Edgar Schoen has pointed out in one of his poems, the intact penis will belong to the sons of Berkeley professors and the "genital chic" (Schoen, 1987). It is also quite unlikely that economic factors and access to medication alone would explain the four-fold difference between the 4.7 percent of normal men and 22.7 percent of circumcised men who reported using medications for erectile dysfunction. We likewise doubt that statements on anti-circumcision websites had any influence on whether a man has erectile dysfunction or his willingness to report it. Where a man places the blame for such dysfunction does affect whether or not he has dysfunction. Difficulty with erections is a common problem in men, but increasingly data are suggesting that the problem is more common in circumcised men.
We are not convinced that Morris and Waskett have presented anything to negate our findings that circumcised men had significantly higher alexithymia scores and were significantly more likely to use medications for erectile dysfunction than normal men. We stand by our findings with the already established caveat that our convenience sample may not be representative of the population at large. We are encouraged that our findings are consistent with the findings of increased rates of sexual difficulties in circumcised men seen in a national health survey (Frisch. Lindhohn, & Gronbaek, 2011). Perhaps Morris and Waskett should let the full research process play itself out by considering testing a similar hypothesis in a more random sampling of the population. After all, it is better to light a candle than to curse the darkness.
Anand, K.J., Runeson, B., & Jacobson, B. (2004). Gastric suction at birth associated with long-term risk for functional intestinal disorders in later life. Journal of Pediatrics, 144, 449-454.
Castellsague, X., Bosch, F.X., Munoz, N., Meijer, C.J.L.M., Shah, K.V., de Sanjose, S., et al. (2002). Male circumcision, penile human papillomavirus infection, and cervical cancer in female partners. New England Journal of Medicine, 346, 1105-1112.
Frisch, M., Lindholm, M., & Gronbaek, M. (2011). Male circumcision and sexual function in men and women: A survey-based, cross-sectional study in Denmark. International Journal of Epidemiology, 40, 1367-1381.
Jacobson, B., & Bygdeman, M. (1998). Obstetric care and proneness of offspring to suicide as adults: Case-control study. British Medical Journal, 317, 1346-1349.
Jacobson, B., Eklund, G., Hamberger, L., Linnarsson, D., Sedvall, G., & Valverius, M. (1987). Perinatal origin of adult self-destructive behavior. Acre Psychiatrica Scandinavica, 76, 364-371.
Jacobson, B., Nyberg, K., Eklund, G., Bygdeman, M., & Rydberg, U. (1988). Obstetrical pain medication and eventual adult amphetamine addiction in offspring. Acta Obstetricia et Gynecologica Scandinavica, 67, 677-682.
Jacobson, B., Nyberg, K., Gronbladh, L., Eklund, G., Bygdeman, M., & Rydberg, U. (1990). Opiate addiction in adult offspring through possible imprinting after obstetric treatment. British Medical Journal, 301, 1067-1070.
Kim, D.S., & Pang, M-G. (2007). The effect of male circumcision on sexuality. BJU International, 99, 619-622.
Nyberg, K., Allebeck, P., Eklund, G., & Jacobson, B. (1992). Socio-economic versus obstetric risk factors for drug addiction in offspring. British Journal of Addiction, 87, 1669-1676.
Nyberg, K.. Allebeck, P., Eklund, G., & Jacobson, B. (1993). Obstetric medication versus residential area as perinatal risk factors for subsequent adult drug addiction in offspring. Paediatric and Perinatal Epidemiology, 7, 23-32.
O'Hara, K. & O'Hara, J. (1999). The effect of male circumcision on the sexual enjoyment of the female partner. BJU International, 83(Suppl. 1), 79-84.
Podnar, S. (2012). Clinical elicitation of the penilo-cavernosus reflex in circumcised men. BJU International, 109, 582-585.
Richardson, D., & Goldmeier, D. (2005). Premature ejaculation--does country of origin tell us anything about etiology? Journal of Sex Medicine, 2,508-512.
Schoen, E.J. (1987). "Ode to the circumcised male." American Journal of Diseases of Children, 141, 128.
Taddio, A., Goldbach, M., Ipp, M., Stevens, B. & Koren, G. (1995). Effect of neonatal circumcision on pain responses during vaccination in boys. Lancet, 345, 291-292.
Taddio, A., Katz, J., Ilersich, A.L., & Koren, G. (1997). Effect of neonatal circumcision on pain response during subsequent routine vaccination. Lancet, 349, 599-603.
Tang, W.S., & Khoo, E.M. (2011). Prevalence and correlates of premature ejaculation in a primary care setting: A preliminary cross-sectional study. Journal of Sexual Medicine, 8(7), 2071-2078.
Zornberg, G.L., Buka, B.L., & Tsuang, M.T. (2000). Hypoxic-ischemia-related fetal/neonatal complications and risk of schizophrenia and other nonaffective psychoses: A 19-year longitudinal study. American Journal of Psychiatry, 157, 196-202.
DAN BOLLINGER * AND ROBERT VAN HOWE, MD. MS **
* Independent Men's Issues Researcher, West Lafayette. IN.
** Department of Pediatrics and Human Development, Michigan State University College of Human Medicine.
Correspondence concerning this letter should be addressed to Dan Bollinger, 1970 North River Road. West Lafayette, IN 47906. Email: email@example.com
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