Table 2. Past studies for variability in optical density of macular pigment.

Methods include AF (fundus autofluorescence) and FR (fundus reflectometry).

Authors	Year	Meas. Type	Method	Repetitions	Subjects	Age Range	SD [%]
Delori et al. [40]	2001	Physiological	AF	N/A	159	15 - 80	33.3
Wüstemeyer et al. [41]	2003	Physiological	AF	N/A	109	18 - 75	32.6
Liew etal. [20]	2005	Physiological	AF	N/A	300	18 - 50	39.3
Trieschmann et al. [42]	2006	Physiological	AF	N/A	120	20 - 86	38.0
Delori et al. [40]	2001	Physiological	FR	N/A	159	15 - 80	30.4
Berendschot et al. [43]	2002	Physiological	FR	1–2	289	63 - 73	45.5
Broekmans et al. [44]	2002	Physiological	FR	N/A	376	18 - 75	45.5
Wüstemeyer et al. [41]	2003	Physiological	FR	N/A	109	18 - 75	38.7
Berendschot, van Norren [45]	2004	Physiological	FR	N/A	138	18 - 76	27.1