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Volume 20, Issue 1
Observational research methods. Research design II: cohort, cross sectional, and case-control studies
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Observational research methods. Research design II: cohort, cross sectional, and case-control studies
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Online download statistics by month: January 2003 to September 2024
Abstract
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Jan 2003
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Feb 2003
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Mar 2003
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Apr 2003
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May 2003
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Jun 2003
2
18
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Jul 2003
11
72
20
Aug 2003
11
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8
Sep 2003
12
39
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Oct 2003
23
51
40
Nov 2003
14
75
24
Dec 2003
15
44
18
Jan 2004
20
67
23
Feb 2004
17
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Mar 2004
16
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Apr 2004
14
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33
May 2004
40
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Jun 2004
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Jul 2004
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Aug 2004
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Sep 2004
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Oct 2004
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Nov 2004
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Dec 2004
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Jan 2005
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Feb 2005
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Mar 2005
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Apr 2005
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May 2005
70
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120
Jun 2005
69
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86
Jul 2005
59
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112
Aug 2005
50
410
136
Sep 2005
86
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Oct 2005
150
1223
454
Nov 2005
142
1262
364
Dec 2005
88
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Jan 2006
91
738
234
Feb 2006
100
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262
Mar 2006
98
1075
250
Apr 2006
110
791
220
May 2006
59
809
231
Jun 2006
83
566
192
Jul 2006
65
599
195
Aug 2006
51
768
180
Sep 2006
88
1082
282
Oct 2006
99
1539
444
Nov 2006
103
1097
399
Dec 2006
62
703
210
Jan 2007
72
847
233
Feb 2007
86
958
264
Mar 2007
113
1035
301
Apr 2007
123
835
270
May 2007
83
967
306
Jun 2007
52
628
193
Jul 2007
50
613
130
Aug 2007
40
446
140
Sep 2007
37
777
193
Oct 2007
68
1125
252
Nov 2007
88
981
210
Dec 2007
55
638
163
Jan 2008
61
759
214
Feb 2008
88
918
240
Mar 2008
99
959
293
Apr 2008
72
985
237
May 2008
87
855
216
Jun 2008
78
770
167
Jul 2008
62
569
163
Aug 2008
46
701
190
Sep 2008
82
1064
224
Oct 2008
86
1106
239
Nov 2008
70
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249
Dec 2008
47
669
153
Jan 2009
73
897
191
Feb 2009
64
1236
347
Mar 2009
130
1394
369
Apr 2009
103
1350
311
May 2009
75
1192
260
Jun 2009
80
996
243
Jul 2009
85
834
191
Aug 2009
82
955
247
Sep 2009
99
1620
338
Oct 2009
135
2019
378
Nov 2009
129
1934
436
Dec 2009
137
1658
317
Jan 2010
149
1841
395
Feb 2010
101
2073
575
Mar 2010
115
2342
502
Apr 2010
40
2647
480
May 2010
56
2631
586
Jun 2010
29
2176
506
Jul 2010
29
2167
389
Aug 2010
31
2386
617
Sep 2010
143
3272
557
Oct 2010
140
4089
551
Nov 2010
65
4155
698
Dec 2010
56
2645
578
Jan 2011
80
3144
673
Feb 2011
78
3116
897
Mar 2011
139
3458
881
Apr 2011
165
2642
654
May 2011
137
2488
648
Jun 2011
267
1830
536
Jul 2011
1275
495
207
Aug 2011
1565
616
286
Sep 2011
2183
793
356
Oct 2011
3505
1285
544
Nov 2011
2825
3596
884
Dec 2011
193
4447
854
Jan 2012
305
4671
1061
Feb 2012
288
4677
972
Mar 2012
347
4524
1271
Apr 2012
321
2857
1329
May 2012
373
3314
1636
Jun 2012
347
2896
1488
Jul 2012
449
2548
1406
Aug 2012
496
2221
1278
Sep 2012
615
3119
2062
Oct 2012
857
3650
2509
Nov 2012
869
2601
2710
Dec 2012
677
1574
2088
Jan 2013
1007
1742
2542
Feb 2013
873
1850
2860
Mar 2013
871
1969
3172
Apr 2013
912
2502
3595
May 2013
664
2218
3232
Jun 2013
443
1944
3083
Jul 2013
388
1992
2354
Aug 2013
503
1853
2454
Sep 2013
575
2111
3838
Oct 2013
649
2178
4272
Nov 2013
576
2094
3909
Dec 2013
439
1526
3049
Jan 2014
581
2070
2992
Feb 2014
628
1936
3714
Mar 2014
810
2341
4544
Apr 2014
845
2352
4879
May 2014
664
2433
4120
Jun 2014
595
2085
3647
Jul 2014
537
1704
2428
Aug 2014
611
1943
2449
Sep 2014
764
3406
2960
Oct 2014
776
3410
1939
Nov 2014
754
2660
883
Dec 2014
528
2084
962
Jan 2015
608
1850
2369
Feb 2015
683
2174
2791
Mar 2015
891
2901
3224
Apr 2015
842
2314
3571
May 2015
825
2842
3937
Jun 2015
576
2016
2644
Jul 2015
609
1886
2133
Aug 2015
601
2164
2526
Sep 2015
894
3034
3457
Oct 2015
689
1929
2570
Nov 2015
828
2268
3671
Dec 2015
702
1657
782
Jan 2016
791
1795
704
Feb 2016
813
1769
685
Mar 2016
909
1822
687
Apr 2016
1207
2283
898
May 2016
969
1744
788
Jun 2016
705
1601
638
Jul 2016
532
1572
511
Aug 2016
770
2207
673
Sep 2016
965
2095
839
Oct 2016
1100
2753
1026
Nov 2016
925
2237
926
Dec 2016
858
1593
1199
Jan 2017
924
2167
870
Feb 2017
859
1423
899
Mar 2017
1136
1112
1180
Apr 2017
1021
2115
1437
May 2017
930
1743
2632
Jun 2017
794
1180
2380
Jul 2017
1316
783
2745
Aug 2017
1910
921
3160
Sep 2017
2979
1577
3385
Oct 2017
4035
2289
4376
Nov 2017
4470
2692
3650
Dec 2017
3074
1785
3536
Jan 2018
3405
1966
4210
Feb 2018
3962
2314
3457
Mar 2018
5864
3625
3278
Apr 2018
6441
4422
4086
May 2018
5020
3474
3485
Jun 2018
3150
2270
2979
Jul 2018
2669
1632
2695
Aug 2018
3894
2773
3055
Sep 2018
5311
3932
3734
Oct 2018
6483
4773
4184
Nov 2018
6251
4595
4155
Dec 2018
4862
3606
3288
Jan 2019
5424
4128
3676
Feb 2019
5794
4567
3671
Mar 2019
7263
5489
4360
Apr 2019
7490
5701
4703
May 2019
7586
6106
4584
Jun 2019
5612
4705
3539
Jul 2019
6019
4947
3731
Aug 2019
7161
5893
4114
Sep 2019
8621
7467
4568
Oct 2019
10571
9337
4274
Nov 2019
9667
8457
4003
Dec 2019
7444
6510
3362
Jan 2020
7570
6624
3231
Feb 2020
6463
5723
3869
Mar 2020
6884
6018
3905
Apr 2020
7248
6459
4441
May 2020
5955
5073
3920
Jun 2020
4827
4155
2787
Jul 2020
3988
3346
2321
Aug 2020
3960
3342
1902
Sep 2020
5698
4885
2809
Oct 2020
7688
6559
3226
Nov 2020
6607
5631
3220
Dec 2020
6161
5400
4166
Jan 2021
6548
5849
3844
Feb 2021
6355
5722
5374
Mar 2021
4022
3002
5202
Apr 2021
3188
2238
4515
May 2021
2890
2406
3901
Jun 2021
1638
1620
3629
Jul 2021
1993
1997
3406
Aug 2021
5744
5750
3581
Sep 2021
8348
8336
4039
Oct 2021
10755
10005
4788
Nov 2021
9040
7917
4899
Dec 2021
6394
5658
3746
Jan 2022
7541
6967
3252
Feb 2022
7515
6809
4017
Mar 2022
10018
8781
4689
Apr 2022
8011
6880
3568
May 2022
7747
6653
3639
Jun 2022
6116
5286
2616
Jul 2022
5646
4857
1998
Aug 2022
6903
5489
1843
Sep 2022
10179
8232
2463
Oct 2022
11682
10418
4065
Nov 2022
11621
10365
3752
Dec 2022
7507
6365
3011
Jan 2023
10003
8644
3409
Feb 2023
11580
10396
3479
Mar 2023
12389
11197
3336
Apr 2023
10494
9135
2746
May 2023
12308
11041
2504
Jun 2023
11618
10911
2014
Jul 2023
13782
13121
1741
Aug 2023
12904
12000
1599
Sep 2023
14313
13436
1865
Oct 2023
17014
15798
2289
Nov 2023
18256
16720
2479
Dec 2023
31098
3692
990
Jan 2024
7030
232
234
Feb 2024
13012
451
398
Mar 2024
19076
987
485
Apr 2024
18374
726
451
May 2024
14927
468
324
Jun 2024
13152
281
214
Jul 2024
17066
374
213
Aug 2024
13240
234
120
Sep 2024
14504
275
126
Total
776520
743346
448218
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