Building the Sampling Frame and Selecting Clusters

The sampling frame is the tool used to include a representative selection of communities (clusters) from within the project area.

Step 1: Population data

The sampling frame is constructed with population data from the project area. All communities are listed in alphabetical order, and population figures are added.

Example: Population data

Region	Subregion	Village	Population	Cumulative Population	Cluster
DINGUIRAYE
	BANORA
	1	Banora	590
	2	Boubéré	1638
	3	Boukaria	481
	4	Diarendji	1195
	5	Kolla	894
	6	Loppé Sountoun	1131
	7	Matagania	2499
	8	M'Bonet	1094
	9	Nafadji	1526
	10	N'Baloufara	460
	11	Sénéma Tombo	456
	DIALAKORO
	12	Dar es Salam	950
	13	Dialakoro	3900
	14	Fello Lamou	888
	15	Mossoko	1077
	16	Watagala	1194
	DIATIFERE
	17	Dabatou	1082
	18	Diatiféré	2283
	19	Fadougou	855
	20	Faméré	1016
	21	Fandanda	1180
	22	Mamoudouya	1993
	23	Nanako	1367
	24	Soubékindi	1016
	25	Sourou	1320
	26	Syllaya	849
	27	Wonson	1549
	DINGUIRAYE
	28	Balagnoumaya	1403
	29	Dinguiraye Ville	9016
	30	Héleyabhé	1612
	31	Kambam Halledé	674
	32	Kambam Sabhé	613
	33	Kebali	1917
	34	Kouby Leyséré	491
	35	Koumbia Ley Fello	1281
	36	Lankon	690
	37	Paridji	796
	38	Parawol Diagul	1029
	39	Sébékoro	1677
	40	Tinkisso	776
	GAGNAKALY
	41	Bagui	1117
	42	Béléya	571
	43	Doussoura	545
	44	Gagnakaly	1156
	45	Hérako	637
	46	Kalenko Missira	815
	47	Kella	861
	48	Missa Djalonké	577
	49	Nouhouya	444
	KALINKO
	50	Babila	1509
	51	Bokoty	1095
	52	Diabérémini	2313
	53	Diankourou	1180
	54	Djissouma	1223
	55	Farabato	481
	56	Fodécariah	647
	57	Fognokonko	689
	58	Kalinko	1236
	59	Kansatoh	2492
	60	Lenny Tyewi	401
	61	Louffamissidé	584
	62	Missira	766
	63	Niogo	1036
	64	Santafara	683
	65	Walandama	438
	66	Yalaguéré	908
	LANSANAYA
	67	Dayégbhé	1073
	68	Hansanguéré	671
	69	Lansanaya	824
	70	Santiguia	1201
	71	Tambanoro	890
	72	Wouyagbhé	1018
	SELOUMA
	73	Bosséré	1372
	74	Fadia	627
	75	Kobala	1503
	76	Sélouma	2470
	77	Walawala	2220
		TOTAL	94731

Step 2: Cumulative Population

The population data are then cumulated. As demonstrated below, the population of Banora (590), plus Boubere (1638) is equal to a cumulative population of 2228. When the population of Boukaria (481) is added, the cumulative becomes 2709. This process is continued until the list is complete. In many project areas, the list of villages will be considerably longer than it is in the case used here.

Example: Cumulative population

Region	Sub-region	Village	Population	Cumulative Population	Cluster
DINGUIRAYE
	BANORA
	1	Banora	590	590
	2	Boubéré	1638	2228
	3	Boukaria	481	2709
	4	Diarendji	1195	3904
	5	Kolla	894	4798
	6	Loppé Sountoun	1131	5929
	7	Matagania	2499	8428
	8	M'Bonet	1094	9522
	9	Nafadji	1526	11048
	10	N'Baloufara	460	11508
	11	Sénéma Tombo	456	11964
	DIALAKORO
	12	Dar es Salam	950	12914
	13	Dialakoro	3900	16814
	14	Fello Lamou	888	17702
	15	Mossoko	1077	18779
	16	Watagala	1194	19973
	DIATIFERE
	17	Dabatou	1082	21055
	18	Diatiféré	2283	23338
	19	Fadougou	855	24193
	20	Faméré	1016	25209
	21	Fandanda	1180	26389
	22	Mamoudouya	1993	28382
	23	Nanako	1367	29749
	24	Soubékindi	1016	30765
	25	Sourou	1320	32085
	26	Syllaya	849	32934
	27	Wonson	1549	34483
	DINGUIRAYE
	28	Balagnoumaya	1403	35886
	29	Dinguiraye Ville	9016	44902
	30	Héleyabhé	1612	46514
	31	Kambam Halledé	674	47188
	32	Kambam Sabhé	613	47801
	33	Kebali	1917	49718
	34	Kouby Leyséré	491	50209
	35	Koumbia Ley Fello	1281	51490
	36	Lankon	690	52180
	37	Paridji	796	52976
	38	Parawol Diagul	1029	54005
	39	Sébékoro	1677	55682
	40	Tinkisso	776	56458
	GAGNAKALY
	41	Bagui	1117	57575
	42	Béléya	571	58146
	43	Doussoura	545	58691
	44	Gagnakaly	1156	59847
	45	Hérako	637	60484
	46	Kalenko Missira	815	61299
	47	Kella	861	62160
	48	Missa Djalonké	577	62737
	49	Nouhouya	444	63181
	KALINKO
	50	Babila	1509	64690
	51	Bokoty	1095	65785
	52	Diabérémini	2313	68098
	53	Diankourou	1180	69278
	54	Djissouma	1223	70501
	55	Farabato	481	70982
	56	Fodécariah	647	71629
	57	Fognokonko	689	72318
	58	Kalinko	1236	73554
	59	Kansatoh	2492	76046
	60	Lenny Tyewi	401	76447
	61	Louffamissidé	584	77031
	62	Missira	766	77797
	63	Niogo	1036	78833
	64	Santafara	683	79516
	65	Walandama	438	79954
	66	Yalaguéré	908	80862
	LANSANAYA
	67	Dayégbhé	1073	81935
	68	Hansanguéré	671	82606
	69	Lansanaya	824	83430
	70	Santiguia	1201	84631
	71	Tambanoro	890	85521
	72	Wouyagbhé	1018	86539
	SELOUMA
	73	Bosséré	1372	87911
	74	Fadia	627	88538
	75	Kobala	1503	90041
	76	Sélouma	2470	92511
	77	Walawala	2220	94731
		TOTAL	94731

The sampling frame is basically completed at this point. Now it will be used to assign the distribution of clusters (villages).

Step 3: Clusters

To assign the clusters, it is first necessary to determine a sampling interval and to select a random number.

3.1 Sampling interval

The sampling interval (SI) will be used to systematically assign clusters from the sampling frame. The SI is equal to the total population of the project area (94731), divided by the number of clusters (30). (See the example from the project area.)

Example

SI = Total Population	SI = 94731	SI = 3158
No. Clusters	30

3.2 Random number

The random number is used to determine the starting point for the first cluster. It should have a value in the range between zero and the SI, which is 0 –3158 in the example.

The random number can be generated by an appropriate computer programme (such as EPI Info), drawn from a random number table, or simply taken from a currency note. As the last method is often the simplest in the field, more detail is given below.

Example

Find a banknote and look at the serial number (SO 19801300). Taking the first four numbers, 1-9-8-0, generates a random number that fits in the required range of 0 – 3158.

3.3 Initial cluster

The first cluster corresponds to the village that has a cumulative population equal to or greater than the random number (1980), which is Boubere in the hypothetical project area. The second cluster corresponds to the village that has a cumulative population equal to or greater than the random number plus the sampling interval (1980+3158=5138), which is Loppe Sountoun village.

Example

Cluster # 1 corresponds to cumulative population of 1980 (Boubere)

Cluster # 2 =1980+3158=5138 (Loppe Sountoun)

Cluster # 3 = 5138+3158=8296 (Matagania)

Cluster # 4 = 8296+3158=11454 (Nibalfoura)

Cluster # 5 = 11454+3158=14612 (Dialakoro)

Cluster # 6 = 14612+3158=1770 (Mossoko). and so on

Example: Clusters

Region	Sub-region	Village	Population	Cumulative Population	Cluster
DINGUIRAYE
	BANORA
	1	Banora	590	590
	2	Boubéré	1638	2228	1
	3	Boukaria	481	2709
	4	Diarendji	1195	3904
	5	Kolla	894	4798
	6	Loppé Sountoun	1131	5929	2
	7	Matagania	2499	8428	3
	8	M'Bonet	1094	9522
	9	Nafadji	1526	11048
	10	N'Baloufara	460	11508	4
	11	Sénéma Tombo	456	11964
	DIALAKORO
	12	Dar es Salam	950	12914
	13	Dialakoro	3900	16814	5
	14	Fello Lamou	888	17702
	15	Mossoko	1077	18779	6
	16	Watagala	1194	19973
	DIATIFERE
	17	Dabatou	1082	21055	7
	18	Diatiféré	2283	23338
	19	Fadougou	855	24193	8
	20	Faméré	1016	25209
	21	Fandanda	1180	26389
	22	Mamoudouya	1993	28382	9
	23	Nanako	1367	29749
	24	Soubékindi	1016	30765	10
	25	Sourou	1320	32085
	26	Syllaya	849	32934
	27	Wonson	1549	34483	11
	DINGUIRAYE
	28	Balagnoumaya	1403	35886
	29	Dinguiraye Ville	9016	44902	12, 13, 14
	30	Héleyabhé	1612	46514	15
	31	Kambam Halledé	674	47188
	32	Kambam Sabhé	613	47801
	33	Kebali	1917	49718	16
	34	Kouby Leyséré	491	50209
	35	Koumbia Ley Fello	1281	51490
	36	Lankon	690	52180
	37	Paridji	796	52976	17
	38	Parawol Diagul	1029	54005
	39	Sébékoro	1677	55682	18
	40	Tinkisso	776	56458
	GAGNAKALY
	41	Bagui	1117	57575
	42	Béléya	571	58146
	43	Doussoura	545	58691
	44	Gagnakaly	1156	59847	19
	45	Hérako	637	60484
	46	Kalenko Missira	815	61299
	47	Kella	861	62160	20
	48	Missa Djalonké	577	62737
	49	Nouhouya	444	63181
	KALINKO
	50	Babila	1509	64690
	51	Bokoty	1095	65785	21
	52	Diabérémini	2313	68098
	53	Diankourou	1180	69278	22
	54	Djissouma	1223	70501
	55	Farabato	481	70982
	56	Fodécariah	647	71629	23
	57	Fognokonko	689	72318
	58	Kalinko	1236	73554
	59	Kansatoh	2492	76046	24
	60	Lenny Tyewi	401	76447
	61	Louffamissidé	584	77031
	62	Missira	766	77797	25
	63	Niogo	1036	78833
	64	Santafara	683	79516
	65	Walandama	438	79954
	66	Yalaguéré	908	80862
	LANSANAYA
	67	Dayégbhé	1073	81935	26
	68	Hansanguéré	671	82606
	69	Lansanaya	824	83430
	70	Santiguia	1201	84631	27
	71	Tambanoro	890	85521
	72	Wouyagbhé	1018	86539
	SELOUMA
	73	Bosséré	1372	87911	28
	74	Fadia	627	88538
	75	Kobala	1503	90041
	76	Sélouma	2470	92511	29
	77	Walawala	2220	94731	30
		TOTAL	94731

The methodology for selecting households within the clusters is explained in Unit II, Training handbook: Collecting anthropometric measures of children.

document.write(document.title)

101 Tools for preparing a survey

Useful links