Cowpeas in Northern Ghana and the Factors that Predict Caregivers’ Intention to Give Them to Schoolchildren
Brouwer ID (2013) Cowpeas in Northern Ghana and the Factors that Predict Caregivers' Intention to Give Them
to Schoolchildren. PLoS ONE 8(8): e72087. doi:10.1371/journal.pone.0072087
Cowpeas in Northern Ghana and the Factors that Predict Caregivers' Intention to Give Them to Schoolchildren
Abdul-Razak Abizari 0
Nerisa Pilime 0
Margaret Armar-Klemesu 0
Inge D. Brouwer 0
Thomas Eisele, Tulane University School of Public Health and Tropical Medicine, United States of America
0 1 Division of Human Nutrition, Wageningen University , Wageningen , The Netherlands , 2 Department of Community Nutrition, School of Medicine and Health Sciences, University for Development Studies , Tamale , Ghana , 3 Department of Nutrition, Noguchi Memorial Institute for Medical Research, University of Ghana , Legon , Ghana
Background: Cowpeas are important staple legumes among the rural poor in northern Ghana. Our objectives were to assess the iron and zinc content of cowpea landraces and identify factors that predict the intention of mothers/caregivers to give cowpeas to their schoolchildren. Methods and Findings: We performed biochemical analysis on 14 landraces of cowpeas and assessed the opinion of 120 caregiver-child pairs on constructs based on the combined model of the Theory of Planned Behaviour and Health Belief Model. We used correlations and multiple regressions to measure simple associations between constructs and identify predictive constructs. Cowpea landraces contained iron and zinc in the range of 4.9-8.2 mg/100 g d.w and 2.7-4.1 mg/ 100 g d.w respectively. The landraces also contained high amounts of phytate (477-1110 mg/100 g d.w) and polyphenol (327-1055 mg/100 g d.w). Intention of mothers was strongly associated (rs = 0.72, P,0.001) with and predicted (b = 0.63, P,0.001) behaviour. The constructs, barriers (b = -0.42, P = 0.001) and attitudes towards behaviour (b = 0.25, P,0.028), significantly predicted intention albeit the predictive ability of the model was weak. Conclusions: We conclude that some cowpea landraces from northern Ghana have appreciable amounts of iron and zinc but probably with poor bioavailability. Attitudes towards giving cowpeas and perception of barriers are important predictors of caregivers' intention to give cowpeas to their schoolchildren. Finally our results suggest that increasing knowledge on nutritional benefits of cowpeas may increase health values caregivers hold for their children in support of giving cowpeas to schoolchildren.
Current address; United States Agency for International Development (USAID); Pretoria; Southern Africa
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Funding: Research was supported by the Interdisciplinary Research and Education Fund (INREF) of Wageningen University through the TELFUN (Tailoring food
sciences to Endogenous patterns of Local food supply for FUture Nutrition) Project. The funders had no role in study design, data collection and analysis, decision
to publish, or preparation of the manuscript.
Competing Interests: The authors have declared that no competing interests exist.
Iron-deficiency is of public health significance in developing
countries [1] and likely to co-exist with zinc deficiencies [2,3]. In
northern Ghana, more than two-thirds of schoolchildren are likely
to suffer from iron-deficiency [4]. Long term consequences include
decreased physical work capacity and future productivity [5,6]. An
integration of approaches has been proposed as key to the
reduction in prevalence of iron-deficiency [7,8]. Strategies to fight
iron-deficiency need to be culturally sensitive, acceptable and
carefully linked with the food culture of communities. One of such
strategies is the promotion of the consumption of local staple foods
that are rich in iron. However local staples in settings like northern
Ghana are largely cereals, roots and tubers, and legumes, which
often do not contain high native iron. Therefore targeted breeding
for higher concentration of native iron (biofortification) has been
proposed as a sustainable intervention to increase dietary iron
intake [9]. Early in the steps towards such biofortification is the
identification of varieties with high native iron and/or zinc to serve
as breeding parents [10].
Being one of the widely consumed staple crops in Ghana,
cowpeas (Vigna unguiculata (L.) Walp) have received attention as a
candidate crop for biofortification to improve its native iron as well
as zinc concentration. Cowpeas are native to northern Ghana
[11]. They have high nutritional significance due to their good
quality protein content and significant amounts of vitamins and
minerals like iron and zinc [12,13]. Over the years cowpeas have
grown from being regarded as poor mans meat [14] to one that
is consumed across socio-economic strata. Therefore cowpeas may
have the potential to contribute to better iron and nutritional
status.
Even though cowpeas are already an intricate part of the food
culture of northern Ghana [13], it is not known what factors
influence mothers to give cowpeas to their schoolchildren.
Understanding the significant factors that predict cowpea
consumption can provide important insight for the development
of effective interventions leading to increased cowpea consumption
not only within a school feeding programme but also at the
household.
To date, two popular psychosocial theories (Theory of Planned
Behaviour (TPB) and Health Belief Model (HBM)) have found
wide use in explaining influential variables in food-related
behaviours. According to the TPB, behaviour is a conscious act
proximally mediated by intention [15]. The HBM on the other
hand posits that a health behaviour results from a set of core beliefs
[16]. It has been proposed that a combination of these two
complementary theories will help broaden our understanding of
factors that influence dietary behaviour [17,18].
In this paper, as part of the early steps in identifying cowpeas
with potential for biofortification, we assessed the iron and zinc
content of available cowpea landraces in northern Ghana.
Secondly, using a combined model as proposed by Sun et al.
[17], we aimed at identifying factors that influence the intention of
mothers/caregivers to give cowpeas to their schoolchildren.
Materials and Methods
Study Area
This study was conducted in the Tolon-Kumbungu district of
the Northern Region of Ghana. The region is well-suited for
cowpea production and Tolon-Kumbungu district is among the
three top production-processing-consuming sites for cowpea in the
region [19]. The research area is located within the Guinea
Savannah agro-ecological zone and has two distinct seasons; rainy
season (April September) and a dry season (December March)
characterized by relatively high day temperatures (3540uC). The
people of this area are largely subsistence farmers [20]. Two
communities, Kpaligung and Tibung, were purposively selected
because they were participating in a larger nutrition study that
sought to investigate the potential role of cowpeas in improving
iron status through school feeding programme. At the time, these
two communities were the only ones piloting the
governmentsupported school feeding programme in the district.
Study Design and Subjects
Cowpea landrace study. Key informant interviews with 3
farmers and 3 market women were conducted in March 2008 to
identify locally available landraces of cowpeas in the selected
communities and the largest market in the main city, Tamale.
Landraces were identified based on the local knowledge and
experience of local farmers and market women. For each landrace,
a sample of 200 g was collected after cleaning and separating
mixed landraces. Seeds with holes or weevil attack were removed
by hand. All collected samples were kept in transparent polythene
bags and labelled with their corresponding local names as given by
the key informants. The samples were sent to Wageningen
University, The Netherlands, and stored at 220uC pending
analysis.
Cowpea acceptability study. This was a cross-sectional
study conducted in two schools within two communities (Kpalgun
and Tibung) in November 2008. In each school 60 schoolchildren
(612 years) in lower primary (classes 13) were randomly selected
to participate, a sample size assumed to be adequate in research
based on the TPB [21]. The corresponding 120 caregivers of the
selected children were invited for interview and none of them
declined participation. In each of the two schools, children were
randomly selected from a sampling frame of pupils in lower
primary (classes 13). The sampling frame was constructed
separately for each school by pooling the class registers of lower
primary. Inclusion of children in the sampling frame was
independent of whether they were present in or absent from
school on the day of sampling frame construction. If two or more
children were selected from one household, one of them was
randomly selected by lottery to participate in the study. The study
was approved by the Institutional Review Board of Noguchi
Memorial Institute for Medical Research, University of Ghana
(NMIMR-IRB 022/08-09). Each volunteer gave verbal informed
consent prior to participation.
Figure 1. A combined model of the Theory of Planned Behaviour and Health Belief Model with correlation coefficients between
related constructs. Adapted from Sun et al. [17]. *P,0.05; **P,0.01; ***P,0.001 (2-tailed).
doi:10.1371/journal.pone.0072087.g001
Table 1. Operational definition of constructs used to examine factors that predict intention of caregivers to give cowpeas to their
schoolchildren.
Health behaviour identity
Attitudes towards behaviour
External control belief
Operational definition
The caregivers knowledge about the relationship between cowpeas and health, and specifically to malnutrition
and iron-deficiency anaemia
The caregivers subjective perception of her schoolchild being malnourished and anaemic
The caregivers feelings concerning the seriousness of her schoolchild being malnourished and anaemic
The importance caregiver places on the consequences of her schoolchild being malnourished and anaemic
The caregivers opinion of the expected consequence of giving cowpeas to the schoolchild
Favourable or unfavourable disposition of the caregiver towards giving cowpeas to the schoolchild
The caregivers beliefs about costs or negative aspects of cowpea consumption by the schoolchild
Triggers that stimulate the caregiver to give cowpeas to her school child.
The caregivers perceived social pressure to give or not to give the schoolchild cowpeas (who is important for
the behaviour and is the opinion of that person important?)
The caregivers perceived presence of factors that may facilitate or impede giving cowpeas to the schoolchild
The caregivers readiness to give cowpeas to the schoolchild
Giving cowpeas to the schoolchild
Questionnaire Development
An 89-item (grouped into 12 constructs, see Table 1) research
questionnaire was developed along the recommendations of
Francis et al [21] and based on the Theory of Planned Behaviour
[15] and the Health Belief Model [16]. These two models were
combined into the study model as described by Sun et al [17],
Figure 1. Relative to behaviour, constructs were grouped into
internal and external factors. The internal factors were further
grouped into: background and perception, belief and attitude, and
intention. The construct subjective norm, left out of Sun et al.s
Polyphenols2
mg/100 g dry weight
Local name Colour
Dagban tuya white
Apagaba ala1 white
Apagaba ala2 white
Gampabgi 1 brown
Sanzi sabinli brown
Gampabgi 2 black
1Inositol hexaphosphate (IP6).
2Gallic acid equivalent (GAE).
3Not analysed due to insufficient sample.
doi:10.1371/journal.pone.0072087.t002
model, was added to the study model because in an African setting
the values of extended family and community significantly
influence behaviour of an individual [22]. The items included in
each construct were drawn from previous studies [17,23] and
literature review on cowpea attributes from West African countries
(Nigeria, Ghana and Senegal) [2429]. The questionnaire also
included questions concerning background information of the
respondents and their schoolchildren. The items in the 12
constructs were verified in a focus group discussion and pre-tested
in a site similar to the study site. Where applicable, constructs were
modified to suite local knowledge and practice. The questionnaire
was translated into the local language (Dagbani) and administered
by well-trained research assistants who were familiar with the
research area and spoke the local language.
Scale Measurements and Analysis
Individual items, phrased as statements, of each construct
(except Intention and Behaviour) were rated on 5-point Likert [30]
response options: strongly disagree, disagree, neutral (neither
disagree nor agree), agree and strongly agree; recoded as unipolar
Colour of cowpea
Sex of child, male
Age of child, years
Age of caregiver, years
Relationship of caregiver to child
Marital status of caregiver
Education of caregiver
Occupation of caregiver
(+1 to +5) or bipolar (2 to +2) depending on the nature of the
question. The score for each construct was computed as the sum of
individual item scores. The scores for the constructs Attitudes
towards behaviour and Subjective norms were sums of products of
paired items; attitudes6evaluation of attitudes, and normative
beliefs6motivation to comply, respectively. To show negative, neutral or positive
influences, item scores of attitudes and normative beliefs ranged from
2 to 2 and the scores of the evaluation of attitudes and motivation to
comply ranged from +1 to +5. This resulted in a paired-item score
range of 10 to 10. For intention and behaviour, scores were based
on the number of times caregivers intended to or had given
cowpeas to their schoolchildren in the succeeding or preceding
month respectively. Intention was considered high if it was greater
than the median intention score of the group (10 times per month)
and low if it was equal to or lower than the median score.
Cowpea Chemical Analysis
Iron and zinc concentration of cowpeas were measured using
inductively coupled plasma atomic emission spectrophotometer
(ICP-AES, Varian Vista-Pro, Palo Alto, CA, USA) after
microwave digestion with a mixture of hydroflouric and nitric acids
(HNO3-HF-H2O2). Analytical variation was ,6% for both iron
and zinc. Phytic acid determination was done using a modified
Makower method [31] in which the inorganic phosphate liberated
from the phytic acid degradation is measured according to the van
Veldhovens method [32] and expressed as inositol hexaphosphate
(IP6). A modified Folin-Ciocalteau method [33] was used to
measure total polyphenol concentration of the cowpea seeds.
Calculation of Phytate-to-mineral Molar Ratios
The respective phytate-to-iron and phytate-to-zinc molar ratios
for each landrace were calculated as: phytate content of cowpea
(mg)?6601/iron content of cowpea (mg)?561; phytate content of
cowpea (mg)?6601/zinc content of cowpea (mg)?65.41
respectively, where 660, 56 and 65.4 are the molecular weights of
phytate, iron and zinc respectively [34,35].
Statistical Analysis
Data processing and analysis was done in SPSS software
(version 18.0, Armonk, NY, USA). Descriptive statistics were used
to examine background characteristics of study participants,
constructs and cowpea landraces. Students t-test for independent
samples was used to compare the difference in chemical
composition between white and coloured landraces of cowpeas.
Cronbachs alpha was computed as measure of reliability for each
construct. A construct was reliable if Cronbachs alpha was .0.7
[36]. The corrected item-total correlation of all items in a
construct was set at 0.30 [36]. When the item-total correlation was
lower than 0.30 the item was deleted from the construct. As such,
a total of 7 items were deleted from two constructs; one item from
cues to action and 6 items from attitudes towards behaviour.
Spearman correlations were computed to determine association
between related constructs. For constructs that influenced
intention, the Mann-Whitney-U test was used to compare whether
subjects with a high intention to consume cowpea scored
significantly different on any of the constructs from subjects with
a low intention. The Wilcoxon signed rank test was used to test the
differences in the scores of behaviour and intention.
Four multiple linear regression models were used to determine
the relative importance of the predicting constructs for the
following outcomes: health behaviour identity, intention and
behaviour. All models were controlled for background
characteristics of caregivers. Significance value for all tests was set at 0.05
(2tailed).
Model 1: Health behaviour identity = f (Knowledge,
Susceptibility, Severity and Value)
Model 2: Intention = f (Barrier, Health behaviour identity, and
Attitudes towards behaviour)
Model 3: Intention = f (Subjective norms, Control beliefs, and
Cues to action)
Model 4: Behaviour = f (Barrier, Intention)
Iron, Zinc, Phytate and Polyphenol Concentrations of
Cowpea Landraces
A total of 14 landraces were identified as common landraces
from the two communities and the central market. Iron and zinc
concentrations ranged from 4.98.2 mg/100 g d.w and 2.7
4.1 mg/100 g d.w respectively. Phytate and polyphenol
concentrations ranged from 4771110 mg/100 g d.w and 327
1055 mg/100 g d.w respectively (Table 2). With respect to
colour of the cowpeas, there was no significant difference (P.0.05)
24.5 (220, 15.5)
Health behaviour identity
Example of item statement
Cowpeas are a blood giving food
My schoolchild easily becomes sick
Shortage of blood causes poor growth of my schoolchild
The health of my schoolchild is very important to me
I worry about the availability of cowpeas on the market
I am the one who decides to give my school child cowpeas
Important ceremonies like weddings or funerals make my
schoolchild want to eat
(My mother-in-law advices me to give cowpeas to my
schoolchild)6(the opinion of my mother-in-law is
important to me)
How many times do you intend to give cowpeas to your
schoolchild in the coming month
How many times have you given cowpeas to your
schoolchild last month
Attitudes towards behaviour (Cowpeas have a good taste)6(my schoolchild prefers
foods that taste good)
in iron, zinc and phytate concentrations between the white and
coloured landraces. Molar ratios of phytate-to-iron also did not
differ between white and coloured landraces (P.0.05). Coloured
landraces however had significantly higher concentrations of
polyphenols and significantly larger (P,0.05) phytate-to-zinc
molar ratios (Table 3).
Background Characteristics
More than 50% of the children in school were male. Ages of the
school children ranged from 612 years with about one-third in
the age groups 89 years and 1011 years. Majority (61%) of
households indicated that they had more than 10 people in their
households. More than 50% of the caregivers of the school
children were older than 35 years, 61% of them were mothers and
62% were in polygamous marriage. Only 4% of the caregivers
were literate and more than 70% of them were either engaged in
farming or trading as their main economic activity (Table 4).
Knowledge, Attitude and Perceptions of Caregivers
about Cowpeas and Giving Cowpeas to Schoolchildren
Ninety-two percent (92%) of caregivers had the intention to give
cowpeas to their schoolchildren at least once per week within the
referent month while 82% indicated that they had given cowpeas
to their schoolchildren at least once per week within the referent
month. Almost all the caregivers agreed that cowpeas contain iron
(94%), can prevent iron-deficiency (97%) and support growth
(97%) of their schoolchildren. They think of cowpeas as a food that
is nutritious (98%), traditional (97%) and tasty (99%), and adds
variety (97%) to the diet of their schoolchildren. More than half
(57%) of the caregivers however think that cowpeas are not easily
digested by their schoolchildren and leaves them feeling uneasy.
Nevertheless 97% of them said their schoolchildren like to eat
cowpeas. Generally the caregivers agreed that availability on the
market (73%), prices (85%), time required to cook cowpeas (71%),
weevils (70%), high prices (80%) and preservation (81%) were
barriers to giving cowpeas to their school children. In line with
their health-related opinions about cowpeas, 70% of the caregivers
indicated that illness serves as a cue for them to give cowpeas to
their schoolchildren.
Reliability of Constructs and their Correlations
Reliability (Cronbachs a) of the multiple item constructs ranged
from (0.670.88). Except for the construct susceptibility, the
reliability of all other constructs was $0.80. Two of the four
constructs classified as background and perception were
significantly correlated with health behaviour identity; knowledge
(rs = 0.23, P = 0.013) and health value (rs = 0.49, P,0.001). Within
the belief and attitude group of constructs, attitude towards
behaviour (rs = 0.45, P,0.001) and perceived barriers (rs = 0.26,
P = 0.004) showed significant correlations with health behaviour
identity. Attitude towards behaviour correlated (rs = 0.22, P = 0.019)
significantly with intention. None of the three constructs classified
as external factors significantly correlated with caregivers
intention to give cowpeas to schoolchildren. Intention to give
cowpeas to schoolchildren was positively and strongly correlated
(rs = 0.72, P,0.001) with the behaviour of giving cowpeas to
schoolchildren (Table 5).
Since attitudes towards behaviour correlated significantly with
intention, we checked and found that scores were higher for the
high intenders but did not significantly differ the scores of low
intenders (z = 0.64, P = 0.52). All median scores of the items
within attitudes towards behaviour were positive for both the low and
high intenders. Paired comparisons between intention and behaviour
showed that intention to give cowpeas was significantly higher
than the behaviour of giving cowpeas (z = 3.177, P = 0.001). Of
the 120 caregivers interviewed the intention-behaviour paired
observations were: intention.behaviour, n = 62;
intention,behaviour, n = 24; intention = behaviour, n = 34.
Standardized b P
appreciable amount of iron and zinc but also contained high
concentrations of phytate and polyphenols.
The range of values we observed for iron (4.98.2 mg/100 g
d.w) and zinc (2.74.1 mg/100 g d.w) were somewhat lower than
the 5.610.4 mg/100 g d.w and 3.75.4 mg/100 g d.w
respectively observed among cowpea landraces in Benin [37]. Based on
iron and zinc concentrations the results suggest that zanzi zee could
be promoted as the most suitable landrace with the potential to
improve iron intake. However, the phytate and polyphenol
concentrations of the landraces were high but within range of
values reported by Madode et al. [37]. Iron and zinc absorption
are partly influenced by phytate and polyphenol concentration
[35,38].
A proxy measure of iron and zinc bioavailabilty is the molar
ratio of iron-to-phytate and zinc-to-phytate respectively
[34,35,39,40]. Iron-to-phytate and zinc-to-phytate molar ratios
of ,1 and #15 respectively are considered predictive of iron
[40,41] and zinc [34,35] bioavailabilty. As such, all the landraces
have low bioavailable iron. For zinc however, apagaba ala-1 and
dagban tuya are likely to contain zinc with higher bioavalability.
Abizari et al [42] found that iron bioavailability in cowpeas was
,2% and their results suggested that rather than polyphenols,
phytate-to-iron molar ratio may predict the low bioavailability.
Cowpea Acceptability
The second objective was to identify factors that influenced
mothers to give cowpeas to their schoolchildren. We found that
intention of mothers was strongly associated with and predicted
behaviour. Knowledge of mothers about cowpeas and the health values
they hold for their children were together associated with intention
through health behaviour identity and attitudes towards behaviour.
Knowledge and health values also predicted health behaviour
identity. Attitudes towards behaviour and perceived barriers were the two
internal constructs that predicted intention significantly albeit the
predictive ability of the intention models was weak.
Other studies using the combined models of TPB and HBM
[17,23,43] or the TPB alone [44,45] have also shown strong
association between intention and behaviour. The studies that
measured behaviour and intention (cross-sectional or prospective)
have also shown that intention is predictive of behaviour and may
sometimes do so through an interaction with perceived barriers
[23]. This seems to suggest that giving cowpeas to schoolchildren
in northern Ghana may be largely driven by conscious efforts of
mothers. It has however been shown that the proximity between
the measurement of intention and behaviour can influence their
association [46]; measured together (as in our case) can strengthen
the association or, when behaviour is assessed after 5 weeks of
measuring intention, weaken the association [47,48]. However, in
a related study in the same communities, frequency of
consumption of cowpea-based meals at the household level was on average
23 times per week (Abizari, unpublished results), similar to values
recorded here as intention and behaviour. As such, proximity may
have had minimal influence on our measurements of intention and
behaviour.
We did not observe a significant role of external factors
(subjective norms, control beliefs and cues to action) on caregivers
intention to give cowpeas to their schoolchild [23,49]. This partly
demonstrates that cowpeas are well accepted in the research area
[13] and their consumption is not influenced by the opinion of
health workers, husbands, mothers in-law and significant others.
In line with the observations of Sheeran et al. [50], the absence of
external influential factors would suggest that intention to give
cowpeas is more likely to be stable if mothers have favourable
attitudes. We doubt however whether if we had much younger
Predicting Health behaviour Identity, Intention and
Behaviour
The relative contribution of the predictor variables to the
outcome variables for models 14 are shown in Table 6. Model 1
explained 36% of the variance in health behaviour identity and the
constructs knowledge (b = 0.20, P = 0.030) and health values (b = 0.49,
P,0.001) significantly predicted health behaviour identity. Model
2 explained only 8% of the variance in intention and the constructs
barriers (b = 0.42, P = 0.001) and attitudes towards behaviour (b = 0.25,
P,0.028) significantly predicted intention. In model 3, none of the
external factors significantly explained intention. Model 4
accounted for 40% of the variance in behaviour and intention
significantly predicted behaviour (b = 0.63, P,0.001).
Cowpea Landraces
Our first objective was to identify the cowpea landrace (s) that
would be most suitable to promote as source of bioavailable iron
and zinc. We found that the locally available landraces contained
reference children (,2 years) the outcome would have been the
same. From our experience in the area, health workers encourage
mothers of such children to give cowpeas to their children
(especially when they are undernourished) ostensibly to improve
iron status and growth. This may partly explain why we observed
in this study that childs illness is an important cue to give
schoolchildren cowpeas. In our predictive model for behaviour we
also observed age of child was a significant explanatory factor. It
means that if iron-deficiency is presented in the context of illness,
mothers would be more likely to accept a cowpea-based food
promoted to contribute to reduce iron-deficiency.
Similar to the role of intention in the TPB model [15], the health
behaviour identity was expected to mediate between background
and perception constructs and intention in the combined model
used in our study [17]. Our results confirm this mediating role of
health behaviour identity [17,23,43]. In our work it means that the
knowledge of mothers about cowpeas in combination with the health
values they hold for their children made them have positive health
behaviour identity. The positive health behaviour identity in turn yielded
positive attitudes towards giving cowpeas to schoolchildren which
subsequently predicted the intention of mothers to give cowpeas. It
implies that if we reinforce mothers knowledge that cowpeas give
blood and support the growth of schoolchildren coupled with
the positive health values mothers hold for their children, it should
be possible to promote cowpeas as likely vehicles to contribute to
reduce iron-deficiency. Such a promotion may not be completely
successful without addressing the barriers to behavioural intention.
For instance, price of cowpea on the market was one of the
barriers mentioned by caregivers. In their work Mishili et al. [51]
reported that cowpea prices on the market start rising a few
months after harvest. The implication is that rural households who
have run out of cowpea stock may find it expensive to buy. Our
results support the findings of Ndubuaku et al. [27] that
abdominal discomforts, presence of weevils and long cooking
time are barriers to cowpea consumption.
Internal reliability measures of our constructs were generally
good and were within range of values observed by others [23,43].
However, there is no prior indication of the reliability of the
predictive models with regards to giving or intention to give
cowpeas. Two other studies [23,43] in Africa that utilized these
predictive models have shown similar trend in low predictive
abilities of the two models on intention. In our case the low
predictive ability could be attributed to the generic reference to
cowpeas rather than a specific cowpea-based food. In a study on
iron-fortified soy sauce the predictive ability of the intention model
was higher (15).
In summary what we have shown is that cowpea landraces from
northern Ghana contain appreciable amounts of iron and zinc,
but probably with a poor bioavailability. Attitudes towards giving
cowpeas and perception of barriers are important predictors of
mothers intention to give cowpeas to their schoolchildren. We
have also shown that health behaviour identity may mediate but
not predict intention of mothers. Finally our results suggest that
knowledge about cowpeas and health values mothers hold for their
children are key areas to focus attention in order to promote giving
cowpeas to school children.
Acknowledgments
We are grateful to the following teachers for their cooperation during the
survey: I. Norgah (Tibung primary school) and S. Inusah (Kpalgung
primary school). We also thank all the research assistants for their
contribution during data collection.
Conceived and designed the experiments: ARA MAK IDB. Performed the
experiments: ARA NP. Analyzed the data: ARA NP IDB. Wrote the
paper: ARA NP MAK IDB.
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