***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The actual effectiveness rates of natural and barrier methods of family planning are lower than the theoretical ones . If couples accurately defined the limits of the fertile phase and used barriers at that time , then actual effectiveness might increase . A r and omized , controlled clinical trial was initiated to determine the effectiveness of the contraceptive sponge used only during the fertile time and to compare this with sponge use at every intercourse . Recruitment problems and discontinuation forced the early termination of this study , but qualitative information about compliance and acceptability was collected . Common sponge problems were reported as were misuses of the sponge , but problems and misuse were not related . Determination of the fertile phase was reportedly easy , but complaints of and discontinuation for inconvenience occurred . For unplanned pregnancies , contraceptive behaviors around the time of conception are presented Proper r and omisation means little if investigators can not include all r and omised participants in the primary analysis . Participants might ignore follow-up , leave town , or take aspartame when instructed to take aspirin . Exclusions before r and omisation do not bias the treatment comparison , but they can hurt generalisability . Eligibility criteria for a trial should be clear , specific , and applied before r and omisation . Readers should assess whether any of the criteria make the trial sample atypical or unrepresentative of the people in which they are interested . In principle , assessment of exclusions after r and omisation is simple : none are allowed . For the primary analysis , all participants enrolled should be included and analysed as part of the original group assigned ( an intent-to-treat analysis ) . In reality , however , losses frequently occur . Investigators should , therefore , commit adequate re sources to develop and implement procedures to maximise retention of participants . Moreover , research ers should provide clear , explicit information on the progress of all r and omised participants through the trial by use of , for instance , a trial profile . Investigators can also do secondary analyses on , for instance , per- protocol or as-treated participants . Such analyses should be described as secondary and non-r and omised comparisons . Mish and ling of exclusions causes serious method ological difficulties . Unfortunately , some explanations for mish and ling exclusions intuitively appeal to readers , disguising the seriousness of the issues . Creative mismanagement of exclusions can undermine trial validity The St and ard Days Method is a fertility awareness-based method of family planning in which users avoid unprotected intercourse during cycle Days 8 through 19 . A prospect i ve multi-center efficacy trial was conducted to test , in a heterogeneous population , the contraceptive efficacy of the St and ard Days Method .  A total of 478 women , age 18 - 39 years , in Bolivia , Peru , and the Philippines , with self-reported cycles of 26 - 32 days , desiring to delay pregnancy at least one year were admitted to the study . A single decrement multi-censoring life table analysis of the data indicate a cumulative probability of pregnancy of 4.75 % over 13 cycles of correct use of the method , and a 11.96 % probability of pregnancy under typical use . This article describes the study and the results . Results suggest that despite its requirement that couples modify their sexual behavior when the woman is fertile , the St and ard Days Method provides significant protection from unplanned pregnancy and is acceptable to couples in a wide range of setting A prospect i ve study to determine the efficacy of three alternative guidelines for the practice of periodic abstinence ( PA ) for family planning was conducted in Indonesia . The three methods studied were the Billings ovulation method , the Dorairaj modified mucus method , and a local version of the mucus method . For each method , the study encompassed a three-month learning phase and an additional 12-month effectiveness phase . Data from a total of 850 acceptors showed that , despite some variations in the sociodemographic characteristics of the acceptors , the Billings ovulation method had the lowest ( 10.4 per 100 women ) and the local mucus method had the highest ( 26.5 per 100 women ) overall life-table discontinuation rates in the effectiveness phase . One-year life-table unplanned pregnancy rates ranged from 2.5 per 100 women for the Billings method to a high of 11.5 per 100 women for the local method acceptors . Unplanned pregnancy was the main reason for termination During the 13-cycle effectiveness phase of a five-center study of the ovulation method of natural family planning  , there were substantial differences , particularly between the two developed and the three developing countries , in the stated degree of satisfaction with the frequency of intercourse ( most couples were satisfied in Bangalore , Manila , and San Miguel , whereas one-third of the subjects and half of their partners would have preferred more frequent intercourse in Auckl and and Dublin ) and in expressed difficulties associated with abstinence ( e.g. , 62 % had occasional difficulty in Auckl and , 14 % in Bangalore , 55 % in Dublin , 28 % in Manila , and 5 % in San Miguel ) . Cumulative net probabilities of discontinuation due to pregnancy were 1.8 % , 18.6 % , and 54.7 % for couples in whom the male partner 's degree of satisfaction was described as " no difficulty , " " occasional difficulty , " and " always some difficulty , " respectively The final results of a prospect i ve comparative study of two methods of natural family planning  indicate a significant difference in the 12 month net cumulative pregnancy rates between the ovulation and symptothermal methods . These differences are on the order of two to one in favor of the symptothermal method .  Pearl pregnancy rates confirm similar differentials between the two methods . Dropout rates for both methods were high . Lack of interest or dissatisfaction with the method was the major reason for dropout training while pregnancy or desire for pregnancy were the major reasons for dropout during the formal phase of the study This paper describes the evaluation of a new method of natural family planning ( NFP ) in Liberia . The Modified Mucus Method ( MMM ) was developed to address the need for a simple method of charting for poor and illiterate women . The acceptance , use , and cost-effectiveness of the MMM were compared with st and ard NFP methods , the sympto-thermal and ovulation method ( ST/OM ) , used in the same population .The personal discontinuation rate of MMM users was 27.3 per 100 women per year compared with 3.2 among ST/OM users . Unplanned pregnancy rates were low for both MMM and ST/OM , 6.6 and 1.5 respectively . The cost per couple year protection ( CYP ) for MMM was $ 55.80 and for ST/OM $ 56.10 . There were differences in characteristics between MMM and ST/OM clients . The MMM clients were more likely to have attended school and to have used a family planning method previously , and were less likely to be housewives . We conclude that the MMM in Liberia was provided to an inappropriate sample of women , educated and middle-class rather than poor and illiterate . The MMM users were dissatisfied and discontinued at the rate of 44 per 100 women entering per year . This is an unfair evaluation of the MMM because of the unsuitable study population . It is our opinion that the MMM needs more study to become part of the inventory of birth spacing methods .ResuméLe présent exposé décrit l'évaluation d'une nouvelle méthode de planning familial naturel au Libéria . La méthode de modification des glaires ( MMM ) a été mise au point pour satisfaire au besoin de disposer d'une méthode simple pouvant être appliquées par les femmes pauvres et analphabètes . L'acceptation , l'utilisation et l'efficacité de cette méthode par rapport à son coût ont été comparées à celles d'autres méthodes de planning familial naturel , à la méthode sympto-thermique et de l'ovulation ( ST/O ) , appliquées dans cette même population .Le taux d'ab and on de la MMM pour des raisons personnelles s'est élevé à 27,3 par an , alors qu'il était de 3,2 chez les femmes utilisant la méthode ST/O. Le nombre des grossesses non planifiées était faible pour l'une et l'autre des méthodes , soit 6,6 pour la MMM et 1,5 pour la méthode ST/O. Le coût annuel de la protection par couple se situait à $ 55,80 pour la première méthode et à $ 56,10 pour la seconde . Les femmes présentaient des caractéristiques différentes d'un groupe à l'autre . Celles qui utilisaient la MMM étaient plus souvent susceptibles d'avoir été scolarisées et d'avoir auparavant utilisé une méthode de planning familial , et moins susceptibles d'être des ménagères . Nous en avons conclu que la MMM avait été mise à la disposition d'un groupe de femmes éduquées , de classe moyenne , à qui elle ne convenait pas , plutôt qu'à des femmes pauvres et analphabètes . Les utilisatrices n'en étant pas satisfaites , elles avaient ab and onné la méthode à un pourcentage de 44 pour cent femmes l'essayant chaque année . Cette évaluation de la MMM n'est pas valable car cette méthode n'était pas adaptée à la population étudiée . Nous estimons qu'il est nécessaire d'étudier plus en profondeur la MMM si l'on veut qu'elle fasse partie de l'ensemble des méthodes visant à espacer les naissances . ResumenEste trabajo describe la evaluación de un nuevo método de planificación familiar natural ( PFN ) in Liberia . El Método del Moco Modificado ( MMM ) se desarrolló a fin de atender a la necesidad de un método sencillo de registro para mujeres pobres y analfabetas . La aceptación , el uso y la eficacia en función de los costos del MMM se comparó con los métodos estándares de PFN , el Método Sintotérmico y de Ovulación ( ST/OM ) , utilizado en la misma población . La tasa de ab and ono personal de las usuarias del MMM fue 27,3 por cada 100 mujeres por año en comparación con 3,2 entre las usuarios del ST/OM . El costo por protección-año de la pareja en le caso del MMM fue $ 55,80 y el del ST/OM $ 56,10 . Hubo características diferentes entre las usuarias del MMM y del ST/OM . Había más probabilidades de que las usuarias del MMM hubieran asistido a la escuela y utilizado métodos de planificación familiar anteriormente , y menos probabilidades de que fueran amas de casa . Llegamos a la conclusión de que el MMM en Liberia era proporcionado a una muestra inadecuada de mujeres , más bien educadas y de clase media que pobres y analfabetas . Las usuarias del MMM estaban insatisfechas y lo ab and onaron a razón de 44 por cada 100 mujeres que lo adoptaban por año . Esta es una evaluación injusta del MMM debido a lo inadecuado de la población del estudio . Opinamos que el MMM requiere mayores estudios para poder llegar a integrar el inventario de métodos de espaciamiento de nacimientos Data accumulated to date from the Los Angeles study indicate that the total termination rate for 12 months from the beginning of the training period and from formal entry into the study was high for the ovulation method ( OM ) , and symptothermal method ( STM ) . Voluntary withdrawal was the highest single reason for termination in both methods . The 12 month voluntary withdrawal rate , measured from formal entry into the study , was significantly higher for OM users . Pregnancy rates measured from both the beginning of training and formal entry into the study were significantly higher for OM users than for STM users . Complete analysis of the data collected during the study is currently in progress . It is anticipated that some of the causes for the differences in pregnancy rates and withdrawal rates between the two methods can be identified 
    Output:
    
REVIEW ERS ' CONCLUSIONS The comparative efficacy of fertility awareness-based methods of contraception remains unknown .
Despite intensive training and ongoing support , most participants in these trials discontinued prematurely .