Table 3

The impact of prescription drug charges on total prescription drug expenditure

Variable
Expenditures
Studies

Co-payment
-
Hanau and Rizzi [87] (IT, NS, TD, R); Joyce et al. [88] (US, OS, CD, R); Lurk et al. [27] (US, NS, CD, R); Meissner et al. [66] (US, OS, CD, NR); Reeder and Nelson [61] (US, NS, TD, R); Smith [89] (US, OS, CD, R)
Multi-tier formulary (vs. 1- or 2-tiers)
-
Fairman et al. [23] (US, NS, CD, R); Gibson et al. [90] (US, NS, PD, R); Huskamp et al. [24] (US, NS, CD, R); Kamal-Bahl and Briesacher [91] (US, OS, CD, R); Motheral and Fairman [28] (US, NS, CD, R); Motheral and Henderson [63] (US, NS, CD, R); Nair et al. [92] (US, NS, TD, R); Thomas et al. [93] (US, OS, CD, NR)
Co-insurance
-
Alignon and Grignon [94] (FR, OS, CD, NR); Almarsdóttir et al. [95] (IC, NS, TD, R); Klaukka et al. [96] (FI, NS, CD, R); Liebowitz et al. [48] (US, ES, CD, R); Newhouse [49] (US, ES, CD, R)
Deductible
-
Van Vliet [97] (NE, OS, CD, R); Van Vliet [98] (NE, OS, CD, R)
Mixed system
-
Gaynor et al. [99] (US, OS, PD, R); Hong and Shepherd [46] (US, OS, CD, NR); Klick and Stratmann [25] (US, OS, CD, R); Smart and Stabile [100] (CA, NS, CD, R); Thomas et al. [93] (US, OS, CD, NR)
Mixed system
0
Grootendorst [26] (CA, NS, PD, R)
Reference pricing (short-term effect)
-
Anderson et al. [59] (SW, NS, TD, R); Grootendorst et al. [64] (CA, NS, TD, R); Grootendorst et al. [101] (CA, NS, TD, R); Mabasa and Ma [39] (CA, NS, CS, NR); Marshall et al. [42] (CA, NS, TD, R); Narine et al. [44] (CA, NS, TD, NR); Puig-Junoy [102] (SP, NS, TD, R); Schneeweiss et al. [103] (CA, NS, TD, NR)
Reference pricing (short-term effect)
0
Ulrich and Wille [104] (GE, NS, TD, NR)
Reference pricing (long-term effect)
0
Grootendorst and Stewart [105] (CA, NS, TD, R); Marshall et al. [42] (CA, NS, TD, R); Schneeweiss et al. [106] (CA, NS, TD, R)
Change from


     co-payment to co-insurance
-
Contayannis et al. [107] (CA, NS, CD, R)
     co-insurance to deductible and co-insurance
-
Contayannis et al. [107] (CA, NS, CD, R)
Insurance coverage


     Primary (vs. none)
+
Artz et al. [108] (US, OS, CD, R); Danzon and Pauly [109] (US, OS, CD, NR); Gianfrancesco et al. [110] (US, NS, CD, NR); Smith and Garner [111] (US, NS, CD, NR)
     Supplementary (vs. none)
+
Davis et al. [112] (US, OS, CD, NR); Dourgnon and Semet [113] (FR, OS, CD, R); Federman et al. [114] (US, OS, CD, R); Lillard et al. [115] (US, OS, CD, R); Long [116] (US, OS, CD, R); Poisal and Murray [117] (US, OS, CD, NR); Raynaud [118] (FR, OS, CD, R); Stuart et al. [119] (US, OS, CD, R); Weeks [120] (US, NS, CD, NR)
     Supplementary (vs. none)
+
Yang et al. [71] (US, OS, CD, R)
     Supplementary (vs. none)
0
Grignon and Perronin [121] (FR, NS, CD, R)
     Public supplementary (vs. private)
+
Raynaud [118] (FR, OS, CD, R)
Prescription limit
-
Soumerai et al. [37] (US, NS, TD, R)

Country: CA = Canada; FI = Finland; FR = France; GE = Germany; IC = Iceland; IT = Italy; NE = The Netherlands; MC = multiple countries; SP = Spain; SW = Sweden; US = United States

Type of study: ES = experimental study; NS = natural study; OS = observational study

Type of data analyzed: CD = cross-sectional data; TD = time-series data; PD = panel data

Type of statistical analysis used: R = regression techniques; NR = no regression techniques

Gemmill et al. International Journal for Equity in Health 2008 7:12   doi:10.1186/1475-9276-7-12