determinants of contraceptive use in oman

Far East Journal of Theoretical Statistics © 2015 Pushpa Publishing House, Allahabad, India Published Online: March 2015 http://dx.doi.org/10.17654/FJTSJan2015_051_064 Volume 50, Number 1, 2015, Pages 51-64

ISSN: 0972-0863

DETERMINANTS OF CONTRACEPTIVE USE IN OMAN Moza Said Al-Balushi, M. S. Ahmed, M. Mazharul Islam and Md Hasinur Rahaman Khan∗ Sultan Qaboos University Muscat, Oman ∗

ISRT University of Dhaka Bangladesh Abstract Contraceptive use is not popular in Oman because of the traditional sociocultural and religious belief but the contraceptive prevalence rate increases over the years (23.7% in 1995 to 28.9% in 200; World Bank, 2008). The rate of increase is much slower in Oman than in other Arabic countries (in Egypt 48% in 1995 to 60% in 2008; World Bank, 2008). Therefore, it is of natural interest to check which are the factors associated with the women current contraceptive use tendency. This study examines important determinants associated with contraceptive use among ever-married women aged 15-49 in Oman using the 2008 Oman National Reproductive Health Survey (ONRHS) data. Binary logistic regression model is implemented to draw valid conclusions about the effects of determinates of contraceptive use in Oman, which is the first ever type of modeling technique used with the contraceptive binary data in Oman. The analysis finding suggests that age of Received: December 2, 2014; Revised: December 15, 2014; Accepted: January 6, 2015 2010 Mathematics Subject Classification: 62P10. Keywords and phrases: contraceptive, determinants, multilevel logistic regression, ONRHSOman National Reproductive Health Survey.

∗

Corresponding author Communicated by Hafiz M. R. Khan

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M. S. Al-Balushi, M. S. Ahmed, M. M. Islam and M. H. R. Khan the women, region, number of living children, education, place of residence and living arrangement have the most significant effects on contraceptive use among the women. The study also suggests that the concerned body should integrate a strong awareness program by targeting the 15-49 aged currently married women in Oman for achieving more reasonable prevalence rate.

1. Introduction Sultanate of Oman is located in the south eastern corner of the Arabian Peninsula. Its coastal line extends 3,165 kilometers from the Strait of Hormuz in the North to the borders of the Republic of Yemen, overlooking three seas: the Arabian Gulf, Gulf of Oman and the Arabian Sea. The total area of the Sultanate of Oman is approximately 309.5 thousands square kilometers. According to National Center for Statistics and Information (NCSI) estimation, a population of 3.6 million (including 1.5 million expatriates, NCSI (2013)) and the mid-year population for 2012 Omani population have a sex ratio of 103 males per 100 females. It is a young population, about 13.9% and 33.7% of the population are under-5 years and under-15 years, respectively and only 6% are 60 years and over. More than quarter (27.1%) of the total Omani population is females in the reproductive age group (15-49). They represent nearly 55.2% of all females and about 42.9% of them are expected to be married. The 2008 World Health Survey (WHS) has showed that the singulate mean age at first marriage is 29.1 years for males and 26.8 years for females. Oman is a high fertility country (about 5 births per women), like most of the middle-eastern and Arab countries and with a high growth rate. The government of Oman considered the current fertility rate to be high, but would like to maintain it (Sulaiman et al. [12]). Total fertility rate decreased from 6.7 births in 1993 to 3.14 births in year 2005 but started to increase in 2006 and reached 3.7 in 2012. The crude birth rate declined from 50 in 1980 to 24.75 in 2005 then increased to reach 32.1 per 1000 Omani population in 2012. The crude death rate declined from 13.3 in 1980 to 2.53 in 2005 then reached 3.2 per 1000 Omani population in 2012 (MOH, 2012).

Determinants of Contraceptive Use in Oman

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To reduce the population growth and marital fertility, family planning methods have been used for more than thirty years in many regions of the world. It is approved that increased family planning spending are an effective long-term investment in human wealth improvement and family happiness. Contraceptives avoid maternal deaths by decreasing the number of times women go through pregnancy and childbirth. Significant protection for women can be provided by contraceptives which are noticed by preventing unintended pregnancies, which often end in unsafe abortion. Since 1994, like growing number of middle-eastern and other countries facing rapid population growth, Oman has officially and explicitly promoted the idea that couples all should allow an interval of at least three years between births (Eltigani [4]). Before 1994 in Oman, admittance to contraceptives was limited although they have been prescribed by doctors of privet sector. The common of Omanis received their health care in public sector, however, where physicians can only distribute contraceptives just for health reasons. After the birth spacing program has been introduced properly, an extensive range of contraceptive was made easily and freely obtainable throughout the Sultanate government hospital, clinic and health centers. However, they are available in different places in Oman either in mountain settlements by helicopter. Since the program began, the contraceptives have been familiars with Omanis in the way the condom have been openly sold in pharmacies and even some grocery stores. By 2000, birth spacing services were offered at some 150 different locations throughout Oman, with over forty of these equipped with separate room for birth spacing counseling. In 2006, birth spacing clinics booked 15,703 new clients and recorded over 84,000 revisits (Eltigani [4]). It is indicated from reports that by mid-1990s, more than one third of the ever-married women (35%) have ever-married used family planning methods. These percentages are considerably higher than the percentages prevailing during the late 1980s (16%). The data also indicates that, between the late 1980s and the year 2000, the percentages of the married Omani

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M. S. Al-Balushi, M. S. Ahmed, M. M. Islam and M. H. R. Khan

women practicing family planning has more than tripled (from 9% to 32%, Eltigani [4]). In Oman, fast development in education, particularly among female, increase female age at first marriage, important upgrading in women status, quick urbanization, the health improvement and survival of young children and development in economic are the determinants of increasing the percentage of contraceptive methods use. The factors that affect contraceptive use are multifaceted and challenge. Several studies evidently indicate that most women knowledge and use of contraceptive is associated with socio-economic, demographic and other proximate factors (Ali et al. [1] and Nega [11]). This paper provides an analysis of the selected determinants of contraceptive using logistic regression model for studying contraceptive prevalence in Oman from the 2008 ONRHS data. Contraceptive prevalence study has been done using such logistic model recently in many studies (Khan and Raeside [7], Kalam and Khan [5], Khan and Shaw [8, 10]). Model structure including its sound interpretation using contraceptive data has been discussed in Khan [9]. The aims of the paper are to explore the true effect of factors which are affecting the regulation of fertility through contraception. The purpose of this study also includes measuring the influence of the combination of the selected factors on the current contraceptive practice of women in Oman, and emphasis is given to compare the estimates (odds ratios) obtained using logistic regression model. An attempt has also been made to make proper policies and implications on the basis of the findings. 2. Data and Methods The data used in this study come from the 2008 Oman National Reproductive Health Survey (ONRHS). The survey was tagged on to the Oman World Health Survey (OWHS) in 2008 and was designed by the World Health Organization (WHO) as part of comprehensive standardized data collection on population health in different countries. Both the ONRHS and OWHS were implemented by the ministry of health of Oman. The details of OWHS may be seen in Al-Riyami et al. [2]. The ONRHS used a sub-


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sample of 3,703 Omani households out of 5,464 households selected for the 2008 OWHS. The ONRHS considered ever-married Omani women of reproductive age 15 to 49 years and ultimately 4,560 women were successfully interviewed. The sample was used to provide national estimates, as well as separate estimates for both rural and urban areas. The sample of the 2008 ONRHS was selected following a multistage stratified cluster sampling design. Stratification was made on two factors: level of urbanization (urban/rural) and geographical distribution. Administratively, Oman was divided into 10 regions at the time of survey (currently 11 regions). The survey covered all the 10 regions of Oman, dividing into 10 urban and 10 rural strata. Equal sample were selected from all strata, with increased sample from urban Muscat. From each strata, 10 clusters were selected randomly. The 2003 population census Enumeration Areas (EAs) were considered as clusters. The 2003 census has defined the EA as the area assigned for one enumerator. There are a total of 3167 EAs in the country. Each EA contains on average 110 households (both Omani and non-Omani) arranged in two or more enumeration blocks (EBs). Twenty four households were selected systematically from the selected EAs. Study variables The study considered current use of contraceptive methods by currently married non-pregnant women of reproductive age as dependent variable. The current use covers both modern and traditional methods of contraceptive. The variable is categorical: women currently using any of the method coded as 1 and those not currently using any method coded as 0. The explanatory variables considered for this analysis include age of the women, region of residence, number of living children, level of education, place of residence, types of family and economic status. Table 1 represents the contraceptive prevalence rate in Oman by selected socio-economic and demographic factors. It was found that 28.9% of women in Oman are using contraceptive, while 71.1% are not.

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Table 1. Percentage of currently using contraceptive by background characteristics of 15-49 aged women


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The proportion of contraceptive use differed by place of residence. The prevalence of contraceptive use was higher among married women who were residing in urban areas (30.1%) as compared to those in rural area (25.6%). Moreover, women who lived in different regions had different status on the use of contraceptive. The highest proportion (44.7%) of married women using contraceptive was found in Musandam followed by Muscat (37.5%) and the least proportion (17.8%) and (19.2%) of women using contraceptive methods was found in Al-Dakhliyah and North Ash Sharqiyah, respectively. There appeared to be some variation in the proportion of women using contraceptives in different regions of Oman. The highest percentage (35.1%) of using contraceptive for married women was observed in the age group (30-34) followed by the age group (40-44) (32.2%) and the lowest percentage (18.9%) of using contraceptive was observed in the age group (45-49). Table 1 shows that the proportion of married women using contraceptive methods was 35.1% among women who had college or university and who had complete preparatory education. The proportion of women who used contraceptive method was 30.1% among married women who had complete secondary education. On the other hand, 19.2% of women had not educated were using contraceptive methods. With regards to the number of living children, the highest percentage (33%) of women who used contraceptives were those women who had 3-4 children followed by those women who had more than seven (29.3%). Moreover, the least proportion (19.2%) of the married women using contraceptive methods had 5-7 children. Married women were belonged to rich economic status, 30.5% used contraceptive methods and women who were belong to poor economic status, 31.2% used contraceptive methods. Among women with extended family or composite living arrangement, 26.3% used contraceptive methods 31.8% of married women who belong to nuclear family used contraceptive. 3. Analytical Methods The response variable is a binary and hence a binary logistic regression model is a natural choice for modeling. The logistic regression is a special

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case of the exponential family that has the following form:

f ( y, θ, φ ) = exp ⎡ ⎢⎣

( yθ − bθ) + c( y , φ )⎤ , ⎥⎦ α (φ )

(3.1)

where α( . ) , b( . ) and c( . ) are some functions. Under logistic regression,

equation (3.1) becomes the binomial distribution of the form ⎛ n⎞ f ( y, p ) = ⎜ ⎟ p y (1 − p )n − y ⎝ y⎠ p ⎞ ⎡ ⎛ n ⎞⎤ = exp ⎢ y log⎛⎜ ⎟ + n log(1 − p ) + log⎜ ⎟⎥ , − p 1 ⎝ ⎠ ⎣ ⎝ y ⎠⎦

p where θ = log ⎡⎢ i ⎤⎥ with pi as the probability of success. It immediately 1 pi ⎦ − ⎣ follows that the binomial distribution is an exponential family distribution with p ⎛n⎞ θ = log ⎡⎢ i ⎤⎥, b(θ) = n log[1 + exp(θ)], c( y, φ) = log⎜ ⎟ and α(φ) = 1. ⎣1 − pi ⎦ ⎝ y⎠ The relationship between the predictor and response variables is not a linear function in logistic regression that is why it is to use the logit transformation of the probability of success. Consider a collection of k explanatory variables denoted by the vector X ′ = ( X1, X 2 , ..., X k ). The conditional probability that the outcome is present, denoted by P(Y = 1 X ) = p, can then be written as p=

exp(β0 + β1 X1 + " + βk X k ) . 1 + exp(β0 + β1 X1 + " + βk X k )

The logit of having Y = 1 is then modeled as a linear function of the explanatory variables as p ⎤ log ⎡ = β0 + β1 X1 + " + β k X k ; ⎢⎣1 − p ⎥⎦

0 ≤ p ≤ 1,

(3.2)

where β0 is a constant of the equation and β1, ..., βk are the coefficients


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of the k predictor variables. The maximum likelihood estimation is used to estimate the parameters of the model in equation (3.2). 4. Analysis Results

Table 2 represents the results of the test of association between current use of contraceptive and each of the explanatory variables. The analysis suggested that age of the women, region, number of living children, education, place of residence, and living arrangement are statistically likely associated with the use of contraception. Table 2. Association test results between explanatory and dependent variable

Variables

χ 2 -value

Variables

χ 2 -value

Age of women

41.544∗∗∗

Number of children

61.055∗∗ ∗

Place of residence

5.735∗

Region

68.908∗∗∗

Women education

39.031∗∗∗

Economic status Living arrangement

5.598 11.475∗∗∗

Note: ∗∗∗p