Table 2 Attrition of patients using the inclusion/exclusion criteria and assignment to three treatment groups before 1:1:1 matching process.

Number of patients MarketScan database (1/2005-6/2008)

NA

49,042,666

Have at least one COPD Study Drug between Jan 1, 2006 - Jun 30, 2007)

48,879,492

163,174

Omit patients with missing or zero quantity or days supply values on any COPD study prescription claim

2,785

160,389

Require at least one diagnosis for COPD (490.xx-492.xx, 494.xx, 496.xx) in any diagnosis field at any time in the data.

44,560

115,829

Omit patients with RX = 0 on any claims medical during the study period; this is MarketScan's indicator that the pharmacy claims were incomplete or unavailable.

690

115,139

Omit patients with a diagnosis of asthma (ICD-9-CM 493.xx), cystic fibrosis (277.0x), or respiratory tract cancer (160.x-164.x) at any time during the available data.

51,149

63,990

Require 12 months pre/12 months post index continuous eligibility

19,871

44,119

Include only patients aged 40 or older on index date

205

43,914

Have at least 30 days per quarter coverage for index prescription

17,669

26,245

Have at least one prescription for tiotropium, formoterol or salmeterol with treatment patterns that were in keeping with one of the three treatment groups (LABA or LAMA, LABA and LAMA or LABA, LAMA and ICS therapy)

9,689

16,556

Omit patients with missing PLANTYPs in CCAE enrollment data

55

16,501

Omit patients with negative dollar amounts in the NETPAY field.

644

15,857

TOTAL

15,857

Treatment group distribution prior to propensity match:

n

%

   LABA or LAMA group

8,334

52.6

   LABA and LAMA group

592

3.7

   LABA, LAMA, and ICS group

6,931

43.7