Automated Telecommunication to Obtain Longitudinal Follow-up in a Multicenter Cross-sectional COPD Study

Figures & data

Figure 1.  Branching questionnaire with all questions asked to COPDGene study subjects via telephony system, web-survey or manually by clinical coordinators.

Figure 2.  Flow diagram highlighting transmission of data from between COPDGene subject, LFU system, clinical center, and data coordinating center.

Table 1.  Demographics of COPDGene Cohort by GOLD Stage

	Total Cohort	Non-Smoker Controls	Smoker Controls	GOLD Unclassified	GOLD 1	GOLD 2	GOLD 3	GOLD 4
N	10220*	108	4433	1204	818	1919	1153	585
Age, yr	59.6 ± 9.0	62.1 ± 9.2	56.6 ± 8.4	57.1 ± 8.3	61.7 ± 8.9	62.6 ± 8.9	64.4 ± 8.3	63.9 ± 7.6
Male,%	53.2	31.5	52.8	46.3	57.7	53.1	57.8	58.8
African American,%	33.1	7.4	41.1	43.9	23.1	25.1	20.8	19.5

Data are presented as mean ± SD or as a percentage of the group.

Non-smoker and smoker control subjects have a post-bronchodilator and FEV1/FVC ≥ 0.7 and FEV1 ≥ 80% predicted.

GOLD Unclassified subjects have a post-bronchodilator FEV1/FVC ≥ 0.7 and FEV1 < 80% predicted.

*Missing from total - 59 subjects who did not have final group assignment due to failed spirometry.

Figure 3.  Percent of COPDGene subjects who responded by website, telephony, and coordinator call at each survey. Over time, patients were most likely to respond by web site.

Figure 4.  Percent of subjects responding to survey 1 stratified by education level. There was an increase in response rate among subjects with a higher education level.

Figure 5.  Percent of subjects responding to survey 1 stratified by method of follow-up and race. African American's were less likely to respond by web-survey.