Skip to main content

Table 2 Secondary outcome measurement variables, participant level analysis metric and methods of aggregation at specific measurement time points of interest

From: Probiotics in pregnancy: protocol of a double-blind randomized controlled pilot trial for pregnant women with depression and anxiety (PIP pilot trial)

Secondary outcome

Measurement variable

Participant-level analysis metrica

Method of aggregation for each probiotic/placebo treatment arm

Demographic information

History of atopy (mother)

Baseline value

Proportion of participants with positive history of atopy at baseline

History of atopy (father)

Baseline value

Proportion of fathers with positive history of atopy at baseline

History of psychiatric disorders

Baseline value

Proportion of participants with positive history of depression or anxiety disorder at baseline

Number of previous pregnancies

Baseline value

Mean (SD) at baseline

Age

Baseline value

Mean (SD) at baseline

Number of previous children

Baseline value

Mean (SD) at baseline

Type of marital status

Baseline value

Proportion of participants in relationship (i.e. married/living together) at baseline

Employment status

Baseline value

Proportion of participants employed at baseline

Education level

Baseline value

Proportion of participants with primary school, lower secondary vocational education, lower secondary education, higher secondary education, middle level vocational education or tertiary education at baseline

Ethnicity

Baseline value

Proportion of participants whose fathers and mothers were born in the Netherlands at baseline

Current psychiatric diagnosis

Baseline value

Proportion of participants with diagnosis depression, anxiety disorder, none or other at baseline

Breastfeeding

Exclusive or partial breastfeeding

End value

Proportion of participants with exclusive breastfeeding and partial breastfeeding at 4 weeks postpartum (t4)

Maternal medication use and treatment

Number of non- pharmacological treatment(s) (i.e. cognitive behavioral therapy, psychotherapy, rapid eye-movement therapy, psychosocial support)

Baseline value; change from baseline to t1

Proportion of participants receiving non-pharmacological treatment at baseline; proportion of participants starting new non-pharmacological treatment between t0 and t1

Number of pharmacological treatment(s) for depression or anxiety

Baseline value; change from baseline to t1

Proportion of participants receiving antidepressants, anxiolytics, other; proportion of participants starting new pharmacological treatment(s) for depression or anxiety between t0 and t1

Type of general medication used

Baseline value; change from baseline to t1

Proportion of participants taking medication (other than pharmacological treatment for depression or anxiety); proportion of participants who start taking new medication between t0 and t1

Type of food supplement(s) used

Baseline value; change from baseline to t1

Proportion of participants taking food supplements; proportion of participants who start taking new food supplements during the intervention period

Type of vitamin(s) used

Baseline value; change from baseline to t1

Proportion of participants taking vitamins; proportion of participants who start taking new vitamins during the intervention period

Maternal lifestyle

Smoking (yes/no)

Baseline value

Proportion of participants smoking

Alcohol (yes/no)

Baseline value

Proportion of participants drinking alcohol

Pregnancy characteristics

Occurrence of infections during pregnancy

Final value

Proportion of participants reporting infections (i.e. influenza, fever, diarrhea) throughout the study

Delivery characteristics

Gestational age

Final value

Gestational age at delivery

Pregnancy and delivery complications

Number of pregnancy and delivery complications (i.e. hypertensive disorders of pregnancy (pregnancy induced hypertension, preeclampsia, eclampsia, hemolysis - elevated liver enzymes - low platelet count (HELLP) syndrome), gestational diabetes mellitus, preterm birth, cesarean section, retention placentae, hemorrhage postpartum, small or large for gestational age (birth weight < p10 or > p90), puerperal fever, prolonged labor, premature rupture of membranes)

Final value

Proportion of participants diagnosed with pregnancy or delivery complications at delivery

Infant antibiotic use

Number of antibiotics used

Final value

Proportion of infants receiving antibiotics during first month of life

Depression

Edinburgh Postnatal Depression Scale (EPDS) score

Change from baseline to t1 and t4

Mean (SD)/median (IQR)

Depression/cognitive reactivity

Leiden Index of Depression Sensitivity-Revised (LEIDS-R) score

Change from baseline to t1 and t4

Mean (SD)/median (IQR)

Pregnancy related anxiety

Pregnancy Related Anxiety Questionnaire-Revised (PRAQ-R) score

Change from baseline to t1

Mean (SD)/median (IQR)

General anxiety

State-trait Anxiety Inventory (STAI-S) score

Change from baseline to t1 and t4

Mean (SD)/median (IQR)

Pregnancy-related daily hassles

Pregnancy-related daily hassles (PES) score

Change from baseline to t1 and t4

Mean (SD)/median (IQR)

General daily hassles/stress

Daily Hassles List (APL) score

Change from baseline to t1 and t4

Mean (SD)/median (IQR)

Mother to infant bonding

Maternal Antenatal Attachment Scale (MAAS) score

Change from baseline to t1

Mean (SD)/median (IQR)

Maternal Postnatal Attachment Scale (MPAS)

Change from t3 to t4

Mean (SD)/median (IQR)

Biological samples

Maternal fecal samples (microbiota)

Change from baseline to t1

Relative abundance and diversity of bacteria at phylum up to genus level

Maternal vaginal samples (microbiota)

Change from baseline to t1

Relative abundance and diversity of bacteria at phylum up to genus level

Maternal hair (cortisol)

Change from baseline to t1

Mean (SD)/median (IQR)

Fecal sample infant (microbiota)

Change from t3 to t4

Relative abundance of bacteria at phylum up to genus level

Cry diary

Duration (hours/minutes) of crying during 3 days

Final value

Mean (SD)/median (IQR)

  1. aBaseline: t0; time point 1: t1, time point 3: t3, time point 4: t4