(a) Inclusion criteria

	Criteria	Number of patients
1	Number of beneficiaries under 65 at eligibility start	4,729,443
2	>1 breast, ovarian, head and neck, or nonsmall cell lung cancer claim from 1999–2005	56,261
3	>1 chemotherapy treatment within 3 months following a breast, ovarian, head and neck, or nonsmall cell lung cancer diagnosis	14,142
4	>3 months of continuous eligibility prior to the first chemotherapy treatment for the qualifying tumor during which no other chemotherapy treatment was received	11,009
5	>1 diagnosis for peripheral neuropathy following first chemotherapy treatment	1,245
6	Peripheral neuropathy within 9 months of first chemotherapy treatment	525
	Main CAPN sample: no diabetes history	454
	Diabetic CAPN sample	71
	Employee CAPN subsample	78