Phenobarbital (Epilepsy)

Spina bifida

R analysis
id Study   Lib. in paper Exposition period    Study type 
 Control type 
 
Tags OR 95%CI x1/n1 x0/n0 no cases no exposed ROB Ref.
S6321
R26047		 Veiby (Phenobarbital) (Controls exposed to Lamotrigine, sick), 2014 Spina bifida throughout pregnancy population based cohort retrospective exposed to other treatment, sick excluded Adjustment: No 33.86 [0.65;1756.14] C
excluded (control group) 		0/18   0/593 0 18
ref
S6323
R26061		 Veiby (Phenobarbital) (Controls unexposed, sick), 2014 Spina bifida throughout pregnancy population based cohort retrospective unexposed, sick Adjustment: No 30.77 [1.53;618.20] C 0/18   3/3,773 3 18
ref
S5526
R19269		 Van der Pol (Phenobarbital) (Controls unexposed, disease free), 1991 Spina bifida occulta throughout pregnancy prospective cohort unexposed, disease free excluded Adjustment: No Matched 4.74 [0.09;251.42] C
excluded (control group) 		0/12   0/55 0 12
ref
S6824
R19319		 Van der Pol (Phenobarbital) (Controls unexposed, sick), 1991 Spina bifida occulta throughout pregnancy prospective cohort unexposed, sick Adjustment: No 0.59 [0.02;15.81] C 0/12   1/22 1 12
ref
Total 2 studies 4.53 [0.09;216.52] 4 30
x1: number of endpoints among exposed, n1: number of exposed; x0: number of endpoints among non exposed, n0: number of non exposed; C: calculated odds ratio from numbers of events and effectives

Forest plot

StudyTE95% CIn casesn exposedweightROBABCDEF Veiby (Phenobarbital) (Controls unexposed, sick), 2014Veiby, 2014 1 30.77[1.53; 618.20]31851%ROB confusion: criticalROB selection: moderateROB classification: moderateROB missing: moderateROB mesure: moderateROB reporting: moderate Van der Pol (Phenobarbital) (Controls unexposed, sick), 1991Van der Pol, 1991 2 0.59[0.02; 15.81]11249%ROB confusion: criticalROB selection: moderateROB classification: moderateROB missing: lowROB mesure: moderateROB reporting: moderate Total (2 studies) I2 = 67% 4.53[0.09; 216.52]4300.2100.01.0ROB: A: confusion, B: selection, C: classification, D: missing, E: measurement, F: reportinglow,moderate,serious,critical,unclear,

1: Phenobarbital) (Controls unexposed, sick; 2: Phenobarbital) (Controls unexposed, sick;

Sensitivity analysis

SubsetTE95% CIn casesn exposedkI2 Type of studies cohort studiescohort studies 4.53[0.09; 216.52]43067%NAVeiby (Phenobarbital) (Controls unexposed, sick), 2014 Van der Pol (Phenobarbital) (Controls unexposed, sick), 1991 2 case control studiescase control studies 0 Type of controls unexposed, sickunexposed, sick 4.53[0.09; 216.52]43067%NAVeiby (Phenobarbital) (Controls unexposed, sick), 2014 Van der Pol (Phenobarbital) (Controls unexposed, sick), 1991 2 Tags Adjustment   - No  - No 4.53[0.09; 216.52]43067%NAVeiby (Phenobarbital) (Controls unexposed, sick), 2014 Van der Pol (Phenobarbital) (Controls unexposed, sick), 1991 2 All studiesAll studies 4.53[0.09; 216.52]43067%NAVeiby (Phenobarbital) (Controls unexposed, sick), 2014 Van der Pol (Phenobarbital) (Controls unexposed, sick), 1991 20.2100.01.0

Publication bias and p-hacking diagnosis

funnel plot

Funnel plot not drawn. Less than 3 points.

Asymetry test p-value = NaN (by Egger's regression)

not enought points

p values plot

Funnel plot not drawn. Less than 3 points.

Sub-groups analysis using all included studies

excluded 5526, 6321

Sub-groupsTE95% CIn casesn exposedkI2ROB type of controls unexposed controls (disease free or unspecified)unexposed controls (disease free or unspecified) 4.74[0.09; 251.42]-12 -NAVan der Pol (Phenobarbital) (Controls unexposed, disease free), 1991 1 unexposed, sick controlsunexposed, sick controls 4.53[0.09; 216.52]43067%NAVeiby (Phenobarbital) (Controls unexposed, sick), 2014 Van der Pol (Phenobarbital) (Controls unexposed, sick), 1991 2 exposed to other treatment, sick controlsexposed to other treatment, sick controls Out of scale33.86[0.65; 1756.14]-18 -NAVeiby (Phenobarbital) (Controls exposed to Lamotrigine, sick), 2014 10.510.01.0