An objective assessment of the variability in number of drops per bottle of glaucoma medication

Moore, Daniel B.; Beck, Judy; Kryscio, Richard J

doi:10.1186/s12886-017-0473-8

BMC Ophthalmology

Table 2 Mean Number of Drops, Volume and Drop/Volume Ratio per Glaucoma Medication Tested

From: An objective assessment of the variability in number of drops per bottle of glaucoma medication

Drop	Mean # Drops			Mean Bottle Volume			Mean Drop Volume		Mean Drops/mL
Drop	vert	horz	p value	vert	horz	p value	vert	horz	vert	horz	p value
2.5 ml
Travatan	76.3 ± 4.2	102.3 ± 1.5	<0.01	2.57 ± 0.07	2.53 ± 0.04		0.032	0.025	29.66 ± 1.35	40.4 ± 1.07	0.0004
Travaprost	75.3 ± 5.1	72 ± 1		2.46 ± 0.04	2.36 ± 0.07		0.032	0.032	30.6 ± 2.51	30.47 ± 1.14	0.9445
Xalatan	101.3 ± 0.6	83.3 ± 3.1		2.69 ± 0.05	2.70 ± 0.05		0.027	0.032	37.68 ± 0.73	30.90 ± 0.60	0.0002
Latanoprost	86.7 ± 9.3	76.7 ± 5.0		2.37 ± 0.26	2.42 ± 0.13		0.027	0.032	36.59 ± 0.98	31.63 ± 0.76	0.0023
Lumigan	101.7 ± 2.3	81.7 ± 4.0	<0.01	2.50 ± 0.05	2.38 ± 0.08		0.024	0.029	40.61 ± 0.18	34.25 ± 0.63	<0.0001
overall mean	88.3	83.2		2.52	2.48		0.029	0.03
overall median	91	81		2.53	2.46		0.027	0.031
overall ST DEV	12.7	11.08		0.15	0.15		0.004	0.003
5 ml
Lumigan	195.6 ± 4.2	155 ± 1	<0.01	4.97 ± 0.06	4.73 ± 0.06		0.025	0.03	39.4 ± 0.69	32.75 ± 0.22	<0.001
Travaprost	150.3 ± 6.5	139.7 ± 13.7		4.91 ± 0.02	4.78 ± 0.24		0.032	0.035	30.62 ± 1.42	29.15 ± 1.50	0.2859
Travatan	146.3 ± 0.6	189 ± 1	<0.01	4.8 ± 0.04	4.78 ± 0.07		0.033	0.026	30.49 ± 0.82	29.66 ± 1.35	0.0004
Alphagan P	111 ± 1	117 ± 2.6		4.89 ± 0.05	4.72 ± 0.18		0.044	0.04	22.7 ± 0.16	24.82 ± 0.78	0.0102
Combigan	148 ± 2	161.3 ± 3.8		5.02 ± 0.16	4.67 ± 0.07	0.01	0.033	0.029	25.26 ± 1.53	34.57 ± 0.50	0.0003
Timolol Pacific	123 ± 1	147.7 ± 9.6	<0.01	4.88 ± 0.04	4.69 ± 0.10		0.04	0.031	25.21 ± 0.09	25.21 ± 0.09	0.0206
Timolol Hi-Tech	126.7 ± 6.7	149.3 ± 4.0	<0.01	5.09 ± 0.15	5.04 ± 0.13		0.041	0.034	24.89 ± 0.56	29.61 ± 0.633	0.0006
Timolol Sandoz	161.3 ± 3.5	156.3 ± 2.5		4.89 ± 0.04	4.84 ± 0.08		0.03	0.031	33.02 ± 0.92	32.28 ± 0.21	0.2459
Betimol	165.3 ± 0.6	160.7 ± 1.2		5.17 ± 0.035	5.08 ± 0.06		0.031	0.031	32.00 ± 0.14	31.63 ± 0.56	0.3282
Timoptic XE	130.7 ± 7.5	115 ± 9.8	0.004	5.53 ± 0.24	4.9 ± 0.24		0.042	0.043	23.71 ± 2.41	23.45 ± 1.16	0.8734
Timoptic	209.3 ± 5.7	155.3 ± 7.1	<0.01	5.93 ± 0.03	5.66 ± 0.03	0.0003	0.089	0.036	35.28 ± 0.82	27.6 ± 1.21	0.0008
Istalol	154.6 ± 2.1	165.6 ± 2.5		4.72 ± 0.03	4.74 ± 0.09		0.03	0.029	32.77 ± 0.22	34.95 ± 0.32	0.0006
overall mean	151.9	151		5.06	4.89		0.039	0.033
overall median	149	155.2		4.93	4.78		0.033	0.031
overall ST DEV	28.2	20.26		0.34	0.28		0.03	0.005
7.5 ml
Lumigan	294 ± 2.6	236 ± 2	<0.01	7.21 ± 0.06	7.18 ± 0.03		0.024	0.03	40.76 ± 0.56	32.85 ± 0.18	<0.001
8 ml
Simbrinza	180.7 ± 3.1	219.7 ± 6.7	<0.01	7.51 ± 0.03	6.74 ± 0.12	0.0004	0.167	0.031	24.07 ± 0.47	32.58 ± 1.22	0.0003
10 ml
Cosopt	301.7 ± 39.6	242 ± 12.5	<0.01	10.2 ± 0.17	9.58 ± 0.18	0.01	0.033	0.039	29.56 ± 3.66	25.26 ± 1.53	0.1341
Dorz/Tim Hi-Tech	303 ± 1	251.7 ± 10.0	<0.01	9.23 ± 0.34	9.19 ± 0.26		0.031	0.038	32.85 ± 1.22	27.39 ± 0.39	0.0018
Dorz/Tim Bausch	313.3 ± 1.5	293.7 ± 1.5	<0.01	9.22 ± 0.23	8.91 ± 0.21		0.03	0.031	34.01 ± 0.92	32.96 ± 0.65	0.1804
Dorz/Tim Sandoz	315 ± 4.6	271.3 ± 5.8	<0.01	8.93 ± 0.15	8.39 ± 0.29		0.115	0.031	35.27 ± 1.09	32.37 ± 1.03	0.0288
Trusopt	313.3 ± 20.0	236 ± 5.6	<0.01	10.18 ± 0.20	9.60 ± 0.33		0.221	0.051	30.77 ± 1.86	24.59 ± 0.94	0.0068
Dorz Hi Tech	292.7 ± 10.3	261.7 ± 12.9	<0.01	9.54 ± 0.19	9.13 ± 0.29		0.033	0.035	20.92 ± 17.91	28.70 ± 2.21	0.5313
Dorz Bausch	289.7 ± 4.2	289 ± 4.6		9.18 ± 0.26	8.78 ± 0.15		0.032	0.03	31.55 ± 0.61	32.91 ± 0.06	0.0594
Dorz Teva	282 ± 11.5	260 ± 1	<0.01	9.31 ± 0.58	8.69 ± 0.12		0.033	0.034	30.33 ± 0.79	29.91 ± 0.31	0.4423
Dorz Sandoz	193.7 ± 3.79	253.7 ± 15.3	<0.01	9.19 ± 0.12	8.38 ± 0.08	0.0006	0.332	0.034	21.06 ± 0.16	30.26 ± 1.94	0.014
Azopt	254.3 ± 2.1	322 ± 8.9	<0.01	9.42 ± 0.08	8.59 ± 0.04	<0.0001	0.037	0.027	27.01 ± 0.38	37.5 ± 1.08	<0.001
Combigan	270.3 ± 28.4	323.7 ± 17.8	<0.01	9.86 ± 0.21	9.79 ± 0.07		0.034	0.03	27.4 ± 2.50	33.07 ± 1.64	0.0303
Alphagan 0.15%	212.7 ± 3.1	234 ± 3.6	<0.01	9.78 ± 0	9.53 ± 0.09		0.046	0.041	21.75 ± 0.31	24.56 ± 0.16	0.0002
Alphagan 0.1%	216 ± 4	283.3 ± 5.5	<0.01	9.93 ± 0.19	9.61 ± 0.07		0.046	0.037	21.75 ± 0.11	24.80 ± 0.41	0.0002
overall mean	273.7	267.5		9.54	9.09		0.079	0.034
overall median	290	261		9.51	9.02		0.034	0.033
overall ST DEV	42.69	31.07		0.45	0.51		0.119	0.005

The mean number of drops, bottle volume, drop volume and ratio of mean number of drops per bottle volume of three bottles tested for each medication in the vertical and horizontal positions. Medications are grouped by volume and an overall mean, median and standard deviation for all medications of similar volumes are provided. A p-value for medications with a significant difference in mean drop number between the horizontal and vertical position is listed, with significance determined at p = 0.01. A ratio of mean number of drops/mean bottle volume is listed, and any two means that differ by a value of 5.27 or greater are significantly different (p < 0.01). Volume measurements are in milliliters (mL). A bold value indicates a p value of statistical significance

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ISSN: 1471-2415

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