Table 1.

The list of secondary outcomes

Outcome	Corresponding secondary objective	Datasets analysed
		Primary care	Secondary care
Health conditions and symptoms in children	1.
Other allergic and allergy-related conditions:	1.a
Food allergy/intolerance		x
Allergic rhinitis and conjunctivitis		x
>1 allergy related disease (asthma, eczema, food allergy/intolerance, allergic rhinitis and conjunctivitis)		x
Penicillin allergy*		x
Anaphylaxis*		x	x
High risk of anaphylactic reaction (prescribing of automatic injection devices containing epinephrine)*		x
Autoimmune diseases:	1.b
Type 1 diabetes*		x	x
Coeliac disease*		x	x
Juvenile idiopathic arthritis*		x	x
Scleroderma/systemic sclerosis*†		x	x
Inflammatory myopathies*†		x	x
SLE*†		x	x
Autoimmune (idiopathic) ITP*		x	x
Juvenile pernicious (megaloblastic) anaemia*		x	x
Childhood vitiligo*†		x
Infections and inflammation:	1 .c
Neonatal sepsis (early and late onset)			x
Other sepsis*			x
Wheeze		x
Upper respiratory tract infections*		x
Lower respiratory tract infections*		x	x
Bronchiolitis*		x	x
Gastroenteritis*		x	x
Inflammatory bowel disease†		x	x
Urinary tract infections*		x	x
Antibiotic prescribing*		x
Other immune system-related conditions:	1.d
Necrotising enterocolitis			x
Leukaemia*†		x	x
Neurodevelopmental conditions:	1.e
Cerebral palsy		x
Autism spectrum disorder*		x
ADHD*		x
Less specific measures of child health:	1 .f
Colic*		x
Failure to thrive*		x
Healthcare utilisation in children	2.
Primary care consultations*		x
Hospital admissions*			x
Maternal outcomes (6 weeks post partum)	3.
Composite infectious morbidity (wound infection, endometritis/endomyometritis, pelvic abscess, maternal sepsis, death attributed to infection)		x	x
Endometritis/endomyometritis		x	x
Wound infection		x	x
Urinary tract infection/cystitis/pyelonephritis		x	x
Sepsis		x	x
Pelvic abscess		x	x
Maternal death (if infection related)*†			x
Antibiotic prescribing*		x
Length of hospital stay*			x

*Exploratory outcome due to insufficient evidence base, including lack of longitudinal studies investigating the association between microbiota/early antibiotic exposure and outcome of interest;

†Tabulation if the outcome is very rare.

ADHD, attention deficit hyperactivity disorder; ITP, thrombocytopenic purpura; SLE, systemic lupus erythematosus.