. Author manuscript; available in PMC: 2018 Mar 1.

Published in final edited form as: J Acad Nutr Diet. 2017 Mar;117(3):404–421.e36. doi: 10.1016/j.jand.2016.11.016

Table 2.

The effectiveness of lifestyle intervention including nutrition education for diabetes prevention: effect size according to delivery agent (dietitian vs non-dietitian) and delivery channel (in-person vs technology-delivered) over time, in the active intervention and overall (active + maintenance study phases)

Outcome	3 months		6 months		12 months		13–60 months

Active Intervention Phase

Delivery Agent

	Dietitian	Non-dietitian	Dietitian	Non-dietitian	Dietitian	Non-dietitian	Dietitian	Non-dietitian
Weight	−0.27^*** (−0.36, −0.19)^a	−0.20^*** (−0.28, −0.12)^a	−1.40 (−4.05, 1.24)^a	−0.44^*** (−0.56, −0.31)^a	−0.16^*** (−0.24, −0.07)^a	−0.27^*** (−0.45, −0.08)^a	-	-

	96.68^b (95.38, 97.61)^c	90.61^b (86.02, 93.70)^c	99.72^b (99.64, 99.79)^c	90.38^b (84.82, 93.90)^c	84.75^b (71.74, 91.77)^c	95.62^b (92.73, 97.36)^c	-	-

FBG^d	−0.18 (−0.44, 0.07)^a	−0.30^*** (−0.51, −0.10)^a	−1.81 (−5.78, 2.16)^a	−0.35^** (−0.66, −0.04)^a	−0.49 (−1.15, 0.16)^a	0.01 (−0.41, 0.43)^a	-	-

	94.18^b (89.26, 96.85)^c	52.11^b (0.00, 78.51)^c	99.87^b (99.84, 99.90)^c	69.70^b (28.92, 87.08)^c	97.39^b (96.24, 98.19)^c	93.85^b (85.43, 97.41)^c	-	-

2-h BG^e	-	-	0.06^f,^g (−0.08, 0.20)^a	−0.22^**^f,^g (−0.42, −0.01)^a	−1.38 (−3.43, 0.68)^a	−0.08^f (−0.28, 0.12)^a	-	-

	-	-	0^b (-) ^c	0^b (-)^c	99.77^b (99.72, 99.81)^c	78.46^b (30.76, 93.30)^c	-	-

HbA1c^h	-	−0.10^f,^g (−1.43, 1.23)^a	-	−0.16^f,^g (−0.37, 0.04)^a	−0.69^g (−1.52, 0.14)^a		-	-

	-	95.12^b	-	30.99^b (0.00, 75.12)^c	99.77^b (99.72, 99.81)^c		-	-

Delivery Channel

	IPⁱ	TECH^j	IP	TECH	IP	TECH	IP	TECH

Weight	−0.22^*** (−0.28, −0.15)^a	−0.32^*** (−0.50, −0.13)^a	−0.88^*** (−1.21, −0.55)^a	−0.92^** (−1.68, −0.15)^a	−0.15^*** (−0.22, −0.08)^a	−0.63^***^g (−0.97, −0.29)^a	-	-

	96.26^b (95.10, 97.15)^c	85.59^b (73.55,92.15)^c	99.31^b (99.16, 99.43)^c	89.64^b (72.08, 96.16)^c	88.80^b (82.36, 92.90)^c	-	-	-

	IP	TECH	IP	TECH	IP	TECH	IP	TECH

FBG	−0.25^*** (−0.42, −0.07)^a	−0.27^g,^g (−0.87, 0.34)^a	−0.95 (−2.71, 0.80)^a	-	−0.34 (−0.84, 0.15)^a	-	-	-

	88.01^b (80.01, 92.81)^c	78.61^b (31.37, 93.34)^c	99.58^b (99.49, 99.65)^c	-	97.35^b (96.34, 98.09)^c	-	-	-

2-h BG	-	-	−0.03^f (−0.14, 0.09)^a	-	−1.03 (−2.32, 0.26)^a	-	-	-

	-	-	40.72^b (0.00, 79.95)^c	-	99.70^b (99.64, 99.74)^c	-	-	-

HbA1c	-	−0.10^f (−1.43, 1.23)^a	−0.11^f,^g (−0.33, 0.11)^a	-	−0.69^f (−1.52, 0.14)^a	-	-	-

	-	95.12^b (− )^c	34.70^b (0.00, 78.75)^c	-	88.13^b (− )^c	-	-	-

Overall Intervention Phase

Delivery Agent

	Dietitian	Non-dietitian	Dietitian	Non-dietitian	Dietitian	Non-dietitian	Dietitian	Non-dietitian

Weight	−0.26^*** (−0.34, −0.18)^a	−0.20^*** (−0.28, −0.12)^a	−0.99 (−2.11, 0.12)^a	−0.28^** (−0.36, −0.19)^a	−0.30^*** (−0.40, −0.21)^a	−0.26^*** (−0.34, −0.18)^a	−0.24^** (−0.44, −0.04)^a	−0.04^**^f (−0.08, −0.01)^a

	96.44^b (95.09, 97.42)^c	90.61^b (86.02, 93.70)^c	99.60^b (99.50, 99.67)^c	88.51^b (82.73, 92.35)^c	91.72^b (88.29, 94.14)^c	94.71^b (93.06, 95.96)^c	88.13^b (81.51, 92.38)^c	56.71^b (0.00 85.64)^c

FBG	−0.18 (−0.44, 0.07)^a	−0.34^*** (−0.54, −0.14)^a	−1.81^f (−5.78, 2.16)^a	−0.47^**^g (−0.78, −0.15)^a	−0.42^*** (−0.70, −0.14)^a	−0.17 (−0.37, 0.04)^a	−0.21^***^f,^g (−0.29, −0.12)^a	0.04^g (−0.07, 0.15)^a

	94.18^b (89.26, 96.85)^c	53.46^b (1.17, 78.09)^c	99.87^b (99.84, 99.90)^c	69.28^b (35.91, 85.28)^c	95.68^b (94.14, 96.81)^c	87.61^b (80.60, 92.09)^c	0.00^b (0.00, 74.62)^c	0.00^b (0.00, 89.60)^c

2-h BG	-	-	0.06 (−0.08, 0.20)^a	−0.22^*** (−0.42, −0.01)^a	−0.44^*** (−0.51, −0.38)^a	−0.09 (−0.22, 0.05)^a	−0.13^**^g (−0.23, −0.04)^a	0.02^f,^g (−0.09, 0.12)^a

	-	-	-	-	99.65^b (99.58, 99.70)^c	70.10^b (30.02, 87.22)^c	0.00^b (0.00, 79.20)^c	-

	Dietitian	Non-dietitian	Dietitian	Non-dietitian	Dietitian	Non-dietitian	Dietitian	Non-dietitian

HbA1c	−0.10^f (−1.43, 1.23)^a	-	-	−0.16^g (−0.37, 0.04)^a	−0.43^*** (−0.70, −0.16)^a	−0.26^* (−0.55, 0.03)^a	−0.38^***^f,^g (−0.55, −0.20)^a	-

	95.12^b (-)^c	-	-	30.99^b (0.00, 75.12)^c	62.30^b (0.00, 87.33)^c	74.29^b (41.49, 88.71)^c	30.80^b (-)^c	-

Delivery Channel

	IP	TECH	IP	TECH	IP	TECH	IP	TECH

Weight	−0.21^*** (−0.27, −0.15)^a	−0.32^*** (−0.50, −0.13)^a	−0.67^*** (−0.86, −0.48)^a	−0.62^*** (−1.02, −0.22)^a	−0.24^*** (−0.30, −0.18)^a	−0.41^*** (−0.68, −0.14)^a	−0.16^*** (−0.31, −0.01)^a	−0.21^**^g (−0.27, −0.15)^a

	96.09^b (94.89, 97.01)^c	85.59^b (73.55, 92.15)^c	99.02^b (98.83, 99.18)^c	89.18^b (77.50, 94.80)^c	92.81^b (90.83, 94.36)^c	93.66^b (89.35, 96.22)^c	89.01^b (83.33, 92.76)^c	96.09^b (94.89, 97.01)^c

FBG	−0.27^*** (−0.45, −0.10)^a	−0.27^f,^g (−0.87, 0.34)^a	−1.02 (−2.58, 0.53)^a	−	−0.33^*** (−0.55, −0.12)^a	−0.33^** (−0.58, −0.08)^a	−0.13^***^g (−0.20, −0.06)^a

	87.25^b (79.10, 92.22)^c	78.61^b (31.37, 93.34)^c	99.46^b (99.34, 99.55)^c	-	94.96^b (93.53, 96.07)^c	80.32^b (48.11, 92.54)^c	40.58^b (0.00, 73.76)^c	-

2-h BG	-	-	−0.03^f,^g (−0.14, 0.09)^a	-	−0.71^* (−1.42, 0.00)^a	−0.27^**^f,^g (−0.41, −0.13)^a	−0.06^g (−0.13, 0.02)^a	-

	-	-	40.72^b (0.00, 79.95)^c	-	99.49^b (99.40, 99.57)^c	0^b (-)^c	46.63^b (0.00, 78.87)	-

HbA1c	-	−0.10^f (−1.43, 1.23)^a	−0.11^g (−0.33, 0.11)^a	-	−0.40^f,^g (−0.62, −0.18)^a	-	−0.29 (−0.59, 0.01)^a	-

	-	95.12^b (-)^c	34.70^b (0.00, 78.75)^c	-	68.90^b (37.78, 84.46)^c	-	67.99^b (0.00, 91.72)^c	-

The 95% confidence intervals of effect size are in the parenthesis.

I square in heterogeneity test

The 95% confidence intervals of I square

FBG=fasting blood glucose

2-h BG=2-hour blood glucose

The number of studies is less than 4.

Indicates that fixed-effect model was used to calculate the summary mean difference in outcomes.

HbA1c=hemoglobin A1c

ⁱ

IP=in-person intervention

TECH=technology-delivered intervention with/without in-person contact

Statistical significance at 10% level

^**

Statistical significance at 5% level.

^***

Statistical significance at 1% level.

- Insufficient data for meta-analysis