Participant characteristics
The baseline sample consisted of 586 mother-infant dyads (response rate 73.5% among those eligible to participate), approximating the expected national distribution of births across districts and 70:30 split between private and public sector. Of those, 372 (response rate: 63.5%), 383 and 340 mothers respectively participated at the first, fourth and sixth month follow-up. The total number of mothers who completed the BSES-SF scale at 48 hours and 1st first month was 504 and 284 respectively, since with a few exceptions, those who did not initiate breastfeeding or were not breastfeeding at the time of assessment did not respond to the scale. As shown in Table 1, the majority of women were aged 25–29 years (46.3%) and 30–34 (21.0%). Only 6.3% of participating mothers were older than 35 years of age. The percentage in the sample who were of Cypriot origin was 77.2%, which is consistent with official statistics. In terms of educational attainment, 57.3% had either undergraduate or postgraduate tertiary education. For 48.9% of mothers, this was their first child. Among the rest, 44.7% reported previous breastfeeding experience. Even though the true prevalence of exclusive breastfeeding was only 18.8% at 48 hours, 81.9% of mothers reported their intention to breastfeed exclusively and 76.6% to do so for at least six months. It is of note that as many as 55.8% delivered by C/S, which is consistent with officially published data.
Table 1
Participants’ characteristics and perceived breastfeeding self-efficacy by socio-demographic and other characteristics
|
N (%)†
|
BSES-SF
Mean (SD) at 48 hours
|
p‡
|
N (%)†
|
BSES-SF
Mean (SD)
at 1st month
|
p‡
|
Age
|
18–24
|
126 (25.3)
|
3.43 (0.85)
|
0.45
|
62 (23.1)
|
4.04 (0.68)
|
0.94
|
25–29
|
231 (46.4)
|
3.41 (0.90)
|
129 (47.9)
|
4.00 (0.80)
|
30–34
|
108 (21.7)
|
3.31 (0.96)
|
59 (21.9)
|
3.96 (0.91)
|
≥ 35
|
33 (6.6)
|
3.59 (0.90)
|
19 (7.1)
|
4.06 (0.66)
|
Education
|
At most secondary
|
208 (42.6)
|
3.41 (0.90)
|
0.03
|
116 (44.3)
|
4.03 (0.77)
|
0.75
|
Undergraduate
|
162 (33.2)
|
3.51 (0.91)
|
89 (33.9)
|
3.99 (0.76)
|
Postgraduate
|
118 (24.1)
|
3.22 (0.85)
|
57 (21.8)
|
3.94 (0.87)
|
Marital Status
|
Married/Cohabiting
|
484 (97.4)
|
3.39 (0.90)
|
0.34
|
259 (97.0)
|
4.00 (0.79)
|
0.69
|
Other
|
13 (2.6)
|
3.63 (0.86)
|
8 (3.0)
|
4.10 (0.69)
|
Employment Status
|
Full Time
|
324 (65.6)
|
3.35 (0.87)
|
0.16
|
170 (63.9)
|
3.94 (0.82)
|
0.18
|
Part Time
|
55 (11.1)
|
3.54 (0.94)
|
33 (12.4)
|
4.04 (0.68)
|
Unemployed
|
115 (23.3)
|
3.49 (0.92)
|
63 (23.7)
|
4.16 (0.75)
|
Monthly Family Net Income
|
<= €1500
|
202 (45.2)
|
3.44 (0.90)
|
0.46
|
119 (48.8)
|
4.05 (0.72)
|
0.15
|
€1501- €3000
|
178 (39.8)
|
3.33 (0.86)
|
86 (35.2)
|
3.88 (0.86)
|
>= €3001
|
67 (15.0)
|
3.43 (0.94)
|
39 (16.0)
|
4.09 (0.82)
|
Country of Origin
|
Cypriot
|
380 (77.2)
|
3.29 (0.86)
|
< 0.001
|
194 (73.5)
|
3.95 (0.78)
|
0.03
|
Not Cypriot
|
112 (22.8)
|
3.83 (0.88)
|
70 (26.5)
|
4.19 (0.77)
|
Type of Birth
|
Vaginal
|
223 (44.2)
|
3.57 (0.87)
|
< 0.001
|
135 (49.1)
|
4.17 (0.73)
|
0.002
|
C/S w/t Gen Anesthesia
|
213 (42.3)
|
3.23 (0.89)
|
93 (33.8)
|
3.93 (0.81)
|
C/S w Gen Anesthesia
|
68 (13.5)
|
3.37 (0.93)
|
|
47 (17.1)
|
3.72 (0.76)
|
|
Parity
|
First child
|
246 (48.9)
|
3.17 (0.81)
|
< 0.001
|
140 (49.3)
|
3.81 (0.79)
|
< 0.001
|
Multiparous w/t previous BF experience
|
32 (6.4)
|
2.78 (1.01)
|
7 (2.5)
|
3.70 (1.18)
|
Multiparous w/ previous BF experience
|
225 (44.7)
|
3.74 (0.84)
|
137 (48.2)
|
4.23 (0.67)
|
Intention to breastfeed exclusively
|
Yes
|
405 (81.9)
|
3.54 (0.83)
|
< 0.001
|
237 (88.4)
|
4.05 (0.76)
|
0.002
|
No
|
92 (18.5)
|
2.80 (0.94)
|
31 (11.5)
|
3.60 (0.84)
|
Intention to breastfeed exclusively for six months
|
Yes
|
377 (76.6)
|
3.57 (0.82)
|
< 0.001
|
225 (84.9)
|
4.08 (0.75)
|
< 0.001
|
No
|
115 (23.4)
|
2.85 (0.93)
|
40 (15.1)
|
3.53 (0.85)
|
†Total number of breastfeeding mothers who completed the BSES-SF scale at 48 hours and 1st first month: N = 504 and N = 284 respectively. Participants with missing socio-demographic information were excluded from the statistical analysis. The percentage of missing values was generally low and ranged between 0–7% (N = 488–504 and 262–284 respectively), with the exception of family income (N = 447 and 244 respectively); ‡p-values as estimated using independent sample t-test or one-way ANOVA, as appropriate.
|
Internal consistency of BSES-SF
The internal consistency of the scale was estimated by Cronbach’s α at 0.94, which is identical to the one reported in the original study [13] (Dennis, 2003). There was no increase by more than 0.1 in the alpha coefficient in response to the deletion of any items. The inter-item correlations ranged between 0.26 to 0.82, with a mean of 0.55.
Breastfeeding Self-Efficacy by Socio-Demographic Characteristics
The mean breastfeeding self-efficacy score was 3.55 (SD = 0.85) within the first 48 hours and 4.01 (SD = 0.79) at the first month assessment. Table 1 shows mean levels (SD) of BSES scores according to sociodemographic characteristics. A statistically significant difference in mean BSES scores was observed by mode of delivery. Mothers who had vaginal delivery were more likely to report higher levels of BSES at 48 hours (3.57, SD = 0.87) compared to those who gave birth by C/S with (3.37, SD = 0.93) and without general anesthesia (3.23, SD = SD: 0.89; p-value < 0.001). Even though BSES scores were generally higher for all by the first month, a significant difference across different types of delivery was still apparent, corresponding to a moderate effect size in the magnitude of 0.5 SD.
Mothers who intended to EBF for six months reported significantly higher levels of BSES from the first 48 hours (M = 3.37, SD = 0.82 vs M = 2.85, SD = 0.93; p-value < 0.001). With regards to nationality, Cypriot mothers (M = 3.29, SD = 0.86) were more likely to report lower levels of BSES than non-Cypriot mothers (M = 3.83, SD = 0.88; p-value < 0.001). This difference appeared smaller by the first month, but remained statistically significant (p-value = 0.026).
Surprisingly, mothers with postgraduate education had the lowest BSES scores (M = 3.22, SD = 0.85) compared to both mothers with University or College education (M = 3.51, SD = 0.91) as well as those with at most secondary education (M = 3.51, SD = 0.91; p-value = 0.025). By the first month, this difference was no longer apparent and the mean scores of the three groups appear similar.
Validity
Factor validity
The construct validity of the BSES-SF was assessed in Exploratory Factor Analyses – see Table 2. The correlation matrix was adequate with the majority of the correlation coefficients exceeding 0.3. The Kaiser–Meyer–Olkin coefficient for sampling adequacy (KMO) was 0.96, which is above the recommended value of 0.60 and the Bartlett’s test of Sphericity was significant (p-value < 0.001), both suggesting that the data are appropriate for factor analysis. Based on the default criterion of eigenvalues greater than 1.0, the analysis yielded a one-factor solution even though the scree plot was suggestive of a two-dimensional structure.
Table 2
Principal component analysis of the BSES-SF scale
|
I can always…
|
Component 1
|
Component 2
|
1
|
Determine that my baby is getting enough milk
|
|
0.803
|
2
|
Successfully cope with breastfeeding like I have with other challenging tasks
|
|
0.763
|
3
|
Breastfeed my baby without using formula as a supplement
|
|
0.618
|
4
|
Ensure that my baby is properly latched on for the whole feeding
|
|
0.752
|
5
|
Manage the breastfeeding situation to my satisfaction
|
|
0.775
|
6
|
Manage to breastfeed even if my baby is crying
|
|
0.630
|
7
|
Keep wanting to breastfeed
|
0.784
|
|
8
|
Comfortably breastfeed with my family members present
|
0.641
|
|
9
|
Be satisfied with my breastfeeding experience
|
0.721
|
|
10
|
Deal with the fact that breastfeeding can be time-consuming
|
0.788
|
|
11
|
Finish feeding my baby on one breast before switching to the other breast
|
0.574
|
0.512
|
12
|
Continue to breastfeed my baby for every feeding
|
0.687
|
|
13
|
Manage to keep up with my baby’s breastfeeding demands
|
0.653
|
|
14
|
Tell when my baby is finished breastfeeding
|
0.617
|
|
% of variance explained
|
58.5%
|
7.48%
|
Cronbach’s alpha coefficient
|
0.923
|
0.911
|
Table 2 depicts the principal component analysis of the BSES scale. The first component included eight items, explaining 33.5% of the variance. With a few exceptions (e.g. “Tell when my baby is finished breastfeeding”), most items were more likely to tap on Breastfeeding Self-efficacy in terms of the cognitive aspects, such as “Keep wanting to breastfeed”, “Comfortably breastfeed with my family members present” and “Deal with the fact that breastfeeding can be time-consuming”. The second component included the remaining six items, and explained 32.5% of the variance. These were more likely to tap on the technical aspects of breastfeeding management. For example, “Determine that my baby is getting enough milk”, “Ensure that my baby is properly latched on for the whole feeding” and “Manage to breastfeed even if my baby is crying”. One of the items (“Finishing feeding my baby on one breast before switching to the other”) cross-loaded in both components with similar factor loadings.
The tool appears to be tapping on two different aspects of breastfeeding self-efficacy. While these two aspects have been described previously in the literature, calculating an overall score seems to be the most standard approach. Thus, for comparability, the overall score was used for further analyses.
Known-group validity
According to Bandura, previous experiences have a significant influence on self-efficacy [9]. Thus, multiparous mothers with previous breastfeeding experience would be expected to be more likely to have higher BSES compared with primiparous mothers. A known-group comparison analysis was conducted to assess this assumption. As shown in Table 1, mothers with previous breastfeeding experience were more likely to report higher BSES (M = 3.74, SD = 0.84) compared to both primiparas (M = 3.17, SD = 0.81) as well as multiparas without BF experience (M = 2.78, SD = 1.01; <0.001), who appear to have the lowest levels of breastfeeding self-efficacy, even compared to primiparas. The observed difference is statistically as well as clinically significant, as it represents a 0.7 SD difference in mean scores. This difference was still apparent at the first month after discharge.
In a stepwise linear regression analysis, parity along with another five variables were the only ones associated with BSES, explaining 24% of the variance 48 hours postnatally - results not shown in detail. In fact, parity (β = 0.414, 95% CI: 0.264, 0.564; p-value = < 0.001) and intention to EBF (β = 0.642, 95% CI: 0.450–0.834; p-value < 0.001) showed the strongest associations with BSES. Other variables predictive of in-hospital BSES scores were initiation of BF (β = 0.498, 95% CI: 0.133, 0.862; p-value = 0.008), non-Cypriot background (β = 0.422, 95% CI: 0.240, 0.604; p-value < 0.001), vaginal delivery (β = 0.273; 95% CI: 0.120, 0.427; p-value = 0.001) and university, but not postgraduate, education (β = 0.182; 95% CI: 0.022, 0.342; p-value = 0.026).
Concurrent and predictive validity
Concurrent and predictive validity of the scale was evaluated by assessing the differences in BSES scores according to breastfeeding initiation and status at 48 hours and thereafter up to the sixth month of the infants’ life. BSES scores during the first 48 hours were highest among mothers who initiated exclusively breastfeeding while at the clinic (M = 3.92, SD = 0.80) compared to those who were breastfeeding not exclusively (M = 3.29, SD = 0.84) and those not breastfeeding (M = 3.04, SD = 1.09; p-value < 0.001) – see Table 3. A similar stepwise pattern of association with breastfeeding status and BSES scores was observed across all follow-up phases of the study, irrespective of whether the analysis looked at the in-hospital or the 1st month assessment of BSES. Consistently, mothers who were still exclusively breastfeeding at a specific time-point of investigation were those who reported higher on average BSES scores (in-hospital or at 1st month), with progressively lower mean scores observed among mother who were either breastfeeding but not exclusively or not breastfeeding by that point.
Table 3
In-hospital and 1st month BSES mean scores by breastfeeding status at 48 hours and at first, fourth and sixth month.
|
Mean (SD) BSES-SF score
|
|
N
|
48 hours
|
p-value¥
|
N
|
1st month
|
p-value¥
|
According to BF status
|
At 48 hours
|
|
|
|
|
|
|
EBF
|
104
|
3.92 (0.80)
|
< 0.001
|
|
-
|
|
BF
|
365
|
3.29 (0.84)
|
|
|
-
|
|
Non-BF
|
35
|
3.04 (1.09)
|
|
|
-
|
|
At 1st month
|
|
|
|
|
|
|
EBF
|
58
|
3.85 (0.86)
|
< 0.001
|
64
|
4.39 (0.66)
|
< 0.001
|
BF
|
193
|
3.49 (0.84)
|
|
206
|
3.95 (0.75)
|
|
Non-BF
|
70
|
2.96 (0.93)
|
|
14
|
3.23 (0.74)
|
|
At 4th month
|
|
|
|
|
|
|
EBF
|
45
|
3.96 (0.67)
|
< 0.001
|
40
|
4.45 (0.54)
|
< 0.001
|
BF
|
114
|
3.65 (0.82)
|
|
105
|
4.29 (0.65)
|
|
Non-BF
|
184
|
3.15 (0.92)
|
|
111
|
3.60 (0.80)
|
|
At 6th month
|
|
|
|
|
|
|
EBF
|
18
|
3.90 (0.76)
|
< 0.001
|
19
|
4.55 (0.35)
|
< 0.001
|
BF
|
97
|
3.73 (0.79)
|
|
88
|
4.32 (0.62)
|
|
Non-BF
|
213
|
3.23 (0.92)
|
|
142
|
3.71 (0.81)
|
|
¥ p-value of one-way ANOVA
|
Breastfeeding
|
Exclusive Breastfeeding
|
By quartiles of BSES scores at 48 hours
|
|
|
By quartiles of BSES scores at the 1st month
|
|
|
Association of BSES with continuation and exclusivity of breastfeeding
To investigate the association of BSES with BF status, we categorized participating mothers based on their BSES scores at 48 hours and first month into quartiles. At 48 hours, for example, the lowest quartile includes the quarter of women with the lowest scores (range: 1.00-2.71) and the upper quartile, those with the highest scores (range: 4.07-5.00). While not large differences were observed in terms of initiation of breastfeeding according to BSES, as shown in Fig. 1, there appears to be a clear stepwise pattern of association of BSES with EBF and BF continuation up to the sixth month. For instance, among the quartile of mothers with the highest BSES scores, as many as 40% initiated exclusive breastfeeding during their stay at the maternity clinic. In contrast, among the quartile of mothers with the lowest BSES scores only 7.9% initiated EBF (p-value < 0.001). The prevalence of EBF for the two middle groups appeared in-between with 15.1% and 19.0%, respectively. At the first month, among mothers at the upper quartile of in-hospital BSES scores about three times as many as those in the lower quartile were exclusively breastfeeding (30.7% vs 10.4%) and about twice as many as those in the second and third quartile (30.7% vs 14.1% vs 15.4%, respectively). Differences in the prevalence of EBF at the fourth month widened further and only appear to converge by the sixth month, due to a sharper decline in the prevalence of EBF among mothers with the highest in-hospital BSES scores. Similar stepwise patterns were observed when using BSES as reported at the first month to track BF and EBF continuation beyond the first month.
Table 4 presents the odds of BF and EBF according to quartiles of increasing levels of in-hospital or 1st -month BSES as estimated in multivariable logistic regression models. The clear stepwise pattern of association of BF outcomes with BSES irrespective of whether measured at 48 hours or 1st month is apparent even after adjusting for potential confounders such as parity, mode of delivery and social position. For instance, a stepwise increase was observed in the odds of EBF initiation as well as at all other time-points across quartiles of women with increasing levels of BSES at 48 hours. Mothers in the second and third quartile were about two to three times more likely to initiate EBF compared to those in the lowest quartile, while the likelihood of women at the upper quartile to initiate exclusive breastfeeding is 8-times higher (ΟR = 7.89, 95% CI: 3.77–16.49; p-value < 0.001). In the multivariable model, the association appears even stronger with adjOR = 9.94 (95% CI: 3.72–26.58; p-value < 0.001) in the upper quartile.
Table 4:
Odds ratios of breastfeeding and exclusive breastfeeding at 48hours, 1st, 4th and 6th month by quartiles of participants with increasing Breastfeeding Self-Efficacy scores measured at 48hours and at 1st month, as estimated in univariable and multivariable logistic models.
|
Based on 48 hour
assessment of BSES
|
Based on 1st month
assessment of BSES
|
Based on 48 hour
assessment of BSES
|
Based on 1st month
assessment of BSES
|
|
Exclusive Breastfeeding
|
Breastfeeding, even if not exclusively
|
|
Unadjusted OR
(95% CI)
|
Adjusted OR
(95% CI)
|
Unadjusted OR
(95% CI)
|
Adjusted OR
(95% CI)
|
Unadjusted OR
(95% CI)
|
Adjusted OR
(95% CI)
|
Unadjusted OR
(95% CI)
|
Adjusted OR
(95% CI)
|
At 48 hours
|
|
|
|
|
|
|
|
|
Lower Quartile
|
1.00
|
1.00
|
-
|
-
|
1.00
|
1.00
|
-
|
-
|
2nd Quartile
|
2.06 (0.9, 4.6)
|
2.15 (0.8, 5.8)
|
-
|
-
|
5.96 (1.7, 21.0)
|
2.92 (0.7, 12.0)
|
-
|
-
|
3rd Quartile
|
2.73 (1.3, 6.0)
|
3.10 (1.2, 8.2)
|
-
|
-
|
2.15 (0.9, 5.2)
|
1.67 (4.7, 5.9)
|
-
|
-
|
Upper Quartile
|
7.89 (3.8, 16.5)
|
9.94 (3.7, 26.5)
|
-
|
-
|
2.15 (0.9, 5.2)
|
2.20 (0.5, 9.2)
|
-
|
-
|
At 1st month†
|
|
|
|
|
|
|
|
|
Lower Quartile
|
1.00
|
1.00
|
1.00
|
1.00
|
1.00
|
1.00
|
N/A
|
N/A
|
2nd Quartile
|
1.42 (0.5, 3.7)
|
1.52 (0.5, 5.2)
|
2.05 (0.8, 5.5)
|
1.44 (0.5 ,4.6)
|
2.61 (1.3, 5.3)
|
3.18 (1.2, 8.4)
|
|
|
3rd Quartile
|
1.57 (0.6, 4.1)
|
2.08 (0.6, 7.2)
|
1.68 (0.6, 4.6)
|
0.78 (0.2, 2.8)
|
3.08 (1.5, 6.4)
|
3.51 (1.2, 9.9)
|
|
|
Upper Quartile
|
3.82 (1.6, 9.0)
|
5.31 (1.7, 17.1)
|
7.94 (3.2, 19.7)
|
6.05 (2.1, 17.6)
|
5.92 (2.6, 13.5)
|
3.92 (1.3, 11.9)
|
|
|
At 4th month
|
|
|
|
|
|
|
|
|
Lower Quartile
|
1.00
|
1.00
|
1.00
|
1.00
|
1.00
|
1.00
|
1.00
|
1.00
|
2nd Quartile
|
2.74 (0.7, 10.7)
|
4.12 (0.8, 22.1)
|
5.57 (1.2, 26.5)
|
3.61 (0.6, 20.8)
|
1.85 (1.0, 3.6)
|
2.06 (1.0, 4.4)
|
5.80 (2.6, 13.2)
|
7.06 (2.6, 19.0)
|
3rd Quartile
|
4.11 (1.1, 15.3)
|
4.28 (0.8, 22.4)
|
3.78 (0.8, 18.9)
|
2.84 (0.5, 17.4)
|
3.99 (2.1, 7.7)
|
3.75 (1.7, 8.5)
|
9.48 (4.2, 21.7)
|
15.6 (5.4, 45.2)
|
Upper Quartile
|
8.26 (2.4, 28.6)
|
13.66 (2.7, 68.6)
|
14.88 (3.3, 66.5)
|
9.54 (1.8, 51.3)
|
4.49 (2.4, 8.5)
|
4.22 (1.9, 9.4)
|
25.04 (9.8, 63.9)
|
28.40 (9.2, 87.3)
|
At 6th month†
|
|
|
|
|
|
|
|
|
Lower Quartile
|
1.00
|
1.00
|
N/A
|
N/A
|
1.00
|
1.00
|
1.00
|
1.00
|
2nd Quartile
|
1.45 (0.2, 8.9)
|
1.77 (0.2, 21.6)
|
|
|
1.78 (0.8, 3.8)
|
2.11 (0.9, 5.1)
|
4.73 (1.9, 11.6)
|
5.81 (1.9, 17.3)
|
3rd Quartile
|
2.10 (0.4, 11.8)
|
1.74 (0.1, 21.4)
|
|
|
4.71 (2.3, 9.8)
|
5.14 (2.1, 12.5)
|
6.58 (2.7, 16.0)
|
9.81 (3.1, 30.9)
|
Upper Quartile
|
4.25 (0.9, 20.2)
|
8.90 (0.9, 86.9)
|
|
|
3.93 (1.9, 8.0)
|
3.64 (1.5, 8.7)
|
18.81 (7.4, 48.0)
|
21.55 (6.9, 67.5)
|
† N/A: At the sixth month, none of the mothers in the lowest quartile of BSES scores were breastfeeding exclusively. Similarly, all the mothers in the upper quartile of BSES at the first month were breastfeeding, while the sample of non-breastfeeding mothers who completed the BSES at this time point was small; thus, models could not be estimated fully. ‡Adjusted for maternal age, educational attainment, marital status, employment status, family income, parity, country of origin, mode of delivery, previous BF experience, as well as BF at 48 hours in models of breastfeeding outcomes beyond 48 hours.
In relation to EBF continuation, an association with BSES scores at 48 hours was observed throughout the study period, attenuating slightly at the sixth month, possibly due to the small number of women exclusively breastfeeding by that point. Even though fewer than 10% of the mothers at the upper quartile were exclusively breastfeeding at the sixth month, this figure was still about four, three and two times higher compared to the respective figure observed among mothers at the lowest (2.3%), the second (3.3%) and the third quartile (4.7%) of BSES scores respectively. The observed stepwise pattern across increasing quartiles of BSES appeared consistent at all time-points of investigation irrespective of whether the analysis looked at 48-hour or 1st -month BSES scores.
Diagnostic Ability of the Tool
Table 5 shows the results of the ROC analysis for the predicting ability of the BSES –SF tool to identify mothers likely to successfully continue breastfeeding in the long term. In terms of diagnostic ability, the tool appears to perform better when used at the first month and less well when used at 48 hours in terms of predicting BF continuation at 4th and 6th month. For instance, at a cut-off value of 3.96, the Sensitivity and Specificity of the BSES-SF at 1st month for BF continuation at 4th month is 79.7% and 63.7%, respectively. The positive and negative predictive value are 74.8% and 71.3%, respectively.
Table 5
Receiver Operating Characteristics (ROC) Analysis of Breastfeeding Continuation at 4th and 6th month as measured by the BSES-SF at 48 hours and 1st month.
|
Breastfeeding
at 4th month
|
Exclusive breastfeeding
at 4th month†
|
Breastfeeding
at 6th month
|
|
BSES at 48 hours
|
BSES at 1st month
|
BSES at 48 hours
|
BSES at 1st month
|
BSES at 48 hours
|
BSES at 1st month
|
AUC (SE)
|
0.666
(0.035)
|
0.779
(0.030)
|
0.696
(0.042)
|
0.707 (0.045)
|
0.646
(0.036)
|
0.755
(0.032)
|
Optimal cut-off
|
3.40
|
3.96
|
3.96
|
3.96
|
3.40
|
3.96
|
Sensitivity (%)
|
70.3
|
79.7
|
63.9
|
91.7
|
73.0
|
81.0
|
Specificity (%)
|
58.8
|
63.7
|
70.0
|
44.8
|
55.3
|
56.1
|
Positive predictive value (%)
|
59.7
|
74.8
|
24.6
|
22.4
|
48.0
|
58.9
|
Negative predictive value (%)
|
68.5
|
71.3
|
93.1
|
97.4
|
79.0
|
79.6
|
† The number of mothers who breastfed exclusively at the 6th month was too small to allow meaningful estimation of the ROC model
|