Table 1. Demographics and potential confounders stratified by exposure (receipt of peer counseling) and outcome (cessation of human milk at discharge)
Peer Counseling / Cessation of Human Milk at Discharge║Yes (n=144) / No (n=256) / p value / Yes (n=108) / No (n=191) / p value
Infant Characteristics
Gestational age (mean, SD)* / 29.8 (3.2) / 30.6 (3.1) / <.01 / 29.4 (3.1) / 31.0 (2.8) / <.01
Length of stay (n, %)
≤ 46 days
> 46 days / 70 (48.6)
74 (51.4) / 135 (52.7)
121 (47.3) / .43 / 47 (28.8)
61 (44.9) / 116 (71.2)
75 (55.1) / <.01
Gender†
Male
Female / 63 (44.1)
80 (55.9) / 118 (48.0)
128 (52.0) / .46 / 60 (42.9)
46 (29.9) / 80 (57.1)
108 (70.1) / .02
Singleton†
No
Yes / 33 (23.6)
107 (76.4) / 95 (37.3)
160 (62.7) / <.01 / 37 (36.6)
69 (35.8) / 64 (63.4)
124 (64.2) / .88
Parity
Primiparous
Multiparous / 61 (42.4)
83 (57.6) / 116 (45.3)
140 (54.7) / .57 / 40 (31.2)
68 (39.8) / 88 (68.8)
103 (60.2) / .13
NEC†
Yes
No / 14 (9.7)
130 (90.3) / 8 (3.1)
247 (96.9) / <.01 / 9 (69.2)
99 (34.6) / 4 (30.8)
187 (65.4) / .01
Sepsis†
Yes
No / 28 (19.7)
114 (80.3) / 21 (8.3)
233 (91.7) / <.01 / 18 (60.0)
88 (33.1) / 12 (40.0)
178 (66.9) / <.01
Maternal Characteristics
Age (mean, SD)*, † / 26.6 (7.1) / 31.4 (5.8) / <.01 / 26.5 (6.9) / 31.5 (6.1) / <.01
Ethnicity†
Non-Hispanic
Hispanic / 79 (55.2)
64 (44.8) / 220 (86.3)
35 (13.7) / <.01 / 67 (29.6)
41 (57.7) / 159 (70.4)
30 (42.3) / <.01
Race†
White
Black or Other / 64 (47.8)
70 (52.2) / 159 (65.7)
83 (34.3) / <.01 / 58 (33.7)
42 (36.8) / 114 (66.3)
72 (63.2) / .59
Insurance type†
State
Private / 124 (87.9)
17 (12.1) / 67 (27.1)
180 (72.9) / <.01 / 80 (55.6)
25 (17.2) / 64 (44.4)
120 (82.8) / <.01
Partner support†
Yes
No / 121 (87.1)
18 (12.9) / 241 (96.0)
10 (4.0) / <.01 / 92 (34.1)
10 (50.0) / 178 (65.9)
10 (50.0) / .15
Married†
Yes
No / 34 (23.9)
108 (76.1) / 173 (68.1)
81 (31.9) / <.01 / 27 (17.4)
77 (55.0) / 128 (82.6)
63 (45.0) / <.01
English-speaking†
Yes
No / 126 (88.1)
17 (11.9) / 249 (97.3)
7 (2.7) / <.01 / 102 (36.2)
5 (31.2) / 180 (63.8)
11 (68.8) / .69
Education†
< High school
HS graduate
> High school / 21 (18.6)
51 (45.1)
41 (36.3) / 8 (3.8)
41 (19.7)
159 (76.4) / <.01 / 18 (75.0)
36 (50.7)
35 (23.8) / 6 (25.0)
35 (49.3)
112 (76.2) / <.01
Prenatal care†,‡
Yes
No / 139 (96.5)
5 (3.5) / 251 (98.4)
4 (1.6) / .22 / 99 (34.1)
8 (100.0) / 191 (65.9)
0 (0.0) / <.01
Smoking on admission†
Yes
No / 22 (15.5)
120 (84.5) / 17 (6.7)
238 (93.3) / <.01 / 21 (67.7)
87 (32.5) / 10 (32.3)
181 (67.5) / <.01
Delivery mode†
C/S
Vaginal / 94 (65.7)
49 (34.3) / 196 (77.2)
58 (22.8) / .01 / 79 (36.1)
28 (35.9) / 140 (63.9)
50 (64.1) / .98
Breastfeeding duration goal†
Yes
No / 86 (78.2)
24 (21.8) / 170 (83.7)
33 (16.3) / .22 / 56 (29.0)
20 (55.6) / 137 (71.0)
16 (44.4) / <.01
Major Surgery†
Yes
No / 27 (19.7)
110 (80.3) / 37 (14.9)
212 (85.1) / .22 / 20 (57.1)
83 (32.8) / 15 (42.9)
170 (67.2) / <.01
Lactation contact†§
1-3 times
4-7 times / 39 (28.3)
99 (71.7) / 17 (7.1)
223 (92.9) / <.01 / 30 (68.2)
70 (29.0) / 14 (31.8)
171 (71.0) / <.01
Peer counseling participant
Yes
No / 61 (53.0)
47 (25.5) / 54 (47.0)
137 (74.5) / <.01
*i p value generated from Mann-Whitney U test instead of t-test
† Observations <400; no variables with observations less than 242
‡ p value generated from Fisher’s Exact test instead of chi-square test
§ Lactation consultant contact while infant was in the NICU
║ Row percentages total to 100%
Data are reported as n(%) unless otherwise noted