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Multiple Indicator Cluster Surveys Data Processing Workshop. Built-In and User-Defined Functions. MICS Data Processing Workshop. Built-In Functions. CSPro has a wide range of built-in functions They are not accessible for modification
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Multiple Indicator Cluster SurveysData Processing Workshop Built-In and User-Defined Functions MICS Data Processing Workshop
Built-In Functions • CSPro has a wide range of built-in functions • They are not accessible for modification • Most built-in functions are well-documented in the help system • You can see a list of these functions by searching on “Alphabetical List of Statements and Functions” within the help system’s index tab • We'll discuss some of the other functions which are not documented
Century Month Code (CMC) Makes date calculations easier to handle • January 1900 = CMC 1 • December 1900 = CMC 12 • January 1901 = CMC 13 • April 2000 = CMC 1204 • April 2001 = CMC 1216 • CMC = (Year-1900)*12 + Month
The cmcode Function Purpose: calculate the CMC of a month/year Syntax: cmcode(month,year) Returns: • if month and year valid: CMC of the month/year provided • if month or year is invalid: 9999(invalid means month or year is equal to DK, missing)
The setlb Function Purpose: calculate the lower CMC bound for an event Syntax: setlb(month,year,minimum) Returns: • if month and year valid: CMC of month/year • if month invalid: CMC of 1/year • if year invalid: minimum
The setub Function Purpose: calculate the upper CMC bound for an event Syntax: setub(month,year,maximum) Returns: • if month and year valid: CMC of month/year • if month invalid: CMC of 12/year • if year invalid: maximum
Example of setlb and setub Suppose: WB1M = 98; WB1Y = 1962; Using setlb and setub, set local variables dobLB & dobUB (DOB lower/upper bound) as follows: dobLB = setlb(WB1M,WB1Y,0); 745 dobUB = setub(WB1M,WB1Y,9999); 756
The adjlba Function Purpose: adjust lower CMC bound for an event using a person’s age; i.e., it calculates a minimum date of birth Syntax: adjlba(lcmc,ucmc,di,di,age) Arguments: • lcmc is the lower CMC bound of an event • ucmc is the upper CMC bound of event • di is the CMC date of interview • Let’s denote the result as rlb (resulting lower bound)
The adjlba Function Calculates: rlb = di – age*12 – 11 we subtract 11 (months), because we assume the person just had their birthday and is therefore at the “bottom-end” of their age, with 11 more months to go before having another birthday Returns: • if rlb in lcmc:ucmc rlb • if rlb < lcmc lcmc • if rlb > ucmc -1 Example: woman born 98/1962; her age=47; date of interview = Aug 2009 adjlba (745,756,1316,1316,47) 741; however, this is below the given lcmc, and so rlb will be assigned 745
The adjuba Function Purpose: adjust upper CMC bound for an event using a person’s age; i.e., it calculates a maximum date of birth Syntax: adjuba(lcmc,ucmc,di,di,age) Arguments: • lcmc is the lower CMC bound of event • ucmc is the upper CMC bound of event • di is the CMC date of interview • Let’s denote the result as rub (resulting upper bound)
The adjuba Function Calculates: rub = di - age*12 we make no adjustments to the person’s age, as we assume they are at the “top-end” of their age, with a birthday looming later this month or in the next month Returns: if rub in lcmc:ucmc rub if rub > ucmc ucmc if rub < lcmc -1 Example: woman born 98/1962; her age=47; date of interview = Aug 2009 adjuba (745,756,1316,1316,47) 752; since this is lower than the given ucmc, rlb will be assigned 752
Example of adjlba and adjuba • Suppose • WB1M = 98, WB1Y = 1975 and WB2 = 34 years dobLB = setlb(WB1M,WB1Y,0); 901 dobUB = setub(WB1M,WB1Y,0); 912 • DOI is 06/2009 so di = 1314 • Using the lower and upper ranges in the adjxba functions below, we find that we can narrow the range of possible cmc birth dates to 901-906 rlb=adjlba(dobLB,dobUB,di,di,WB2)901 rub=adjuba(dobLB,dobUB,di,di,WB2)906
User-Defined Function (UDF) • UDFs are defined in the PROC GLOBAL block • These functions do not need to be modified (except functionvdvalid), but they do need to be understood
Data Checking UDFs There are four UDFs that assist with executing arithmetic operations: valid—checks if the value is not a special value, i.e., other (96), inconsistent (97), don’t know (98), or missing (99) NAtoZero—if a question has been skipped (assigning a value of ‘not applicable’ to that question) or is missing, this function will return 0 (zero), so that the question can be used in arithmetic equations notEq—a value-added <> command badspecial—ensures that Unit/Number questions are consistent with one another
The valid UDF Purpose: ensures that a variable has a valid value Syntax: valid (xvar) Returns: 1 if value of xvar is not “special” (i.e., is not equal to notappl) and ≤ 95 0 otherwise
The NAtoZero UDF Purpose: permits one to use variables that could be “not applicable” in arithmetic equations Syntax: NAtoZero(xvar) Returns: 0 if value of xvar is not applicable value of xvar otherwise
The notEq UDF Purpose: A value-added <> check. dvar is passed thru the NAtoZero function first before the <> test is made. Syntax: notEq(xvar,dvar) Returns: 1 if xvar <> NAtoZero (dvar) 0 otherwise
The badspecial UDF Purpose: Ensures that the Unit response is consistent with the Number response Syntax: badspecial(units,number) Returns: 1 if there is a problem, i.e., if U = 9 & N <= 90 or U <> 9 & N in 90:98 or U > 1 & N = 0 0 otherwise
Birth History UDFs • There are three UDFs that concern the birth history • ValidYr – like valid except for 4 digit years • AfterInt – checks if a date is after the date of interview • ndjlba – like adjlba with a slight change
The validyr UDF Purpose: ensures that a year variable has a valid year value Syntax: validyr (xvar) Returns: 1 if value of xvar is not “special” (i.e., is not equal to notappl or missing) and ≤ 9995 0 otherwise
The AfterInt UDF Purpose: ensures that a date is before the date of interview Syntax: AfterInt (vcheckm, vchecky) Returns: 1 if vchecky > year of interview (WM6Y) or, (if vchecky = year of interview (WM6Y) and vcheckm > month of interview (WM6M) ) 0 otherwise
The ndjlba UDF Purpose: adjusts the lower bound a pair of century month code values for a date, based on the age reported (modified version of adjlba). Syntax: ndjlba(lcmc,ucmc,di,di,age) Returns: Same as for adjlba, but it avoids the possibility of producing a CMC that would imply the imputation of an age that is 1 year higher (possible with adjlba).
Anthropometry UDFs • There are seven UDFs that concern anthropometry • The first six of these will not be discussed • The seventh is named agemth • It calculates a child’s age in months
The agemth UDF Purpose: calculates most accurate age in months possible (used for anthropometry) Syntax: agemth(bd,bm,by,id,im,iy) (i.e., child’s DOB and date of interview) Returns: • child’s age in months if child’s birth day, month, and year are valid • child’s age in months using 15 as day if only birth month and year are valid • 9999 if only birth year is valid
Vaccination UDFs • There are four UDFs in the data entry application that check the validity of the vaccination date: vdvalid, vdoi, vdobandvacgiven • There are two more UDFs in the editing program that check the ordering of vaccination dates, which we’ll discuss now: vseq and vmatch
The vdvalid UDF • Purpose: checks if the vaccination date is valid (look for !!! in the logic to adjust dates per your interview period) • Syntax: vdvalid(vday,vmonth,vyear) • Returns: 0 if vaccination date is valid 1 otherwise
The vdoi UDF • Purpose: checks if the vaccination is not after the date of interview • Syntax: vdoi(vday,vmonth,vyear) • Returns: 0 if vaccination date before date of interview 1 otherwise
The vdob UDF • Purpose: checks if the vaccination is not before the date of birth • Syntax: vdob(vday,vmonth,vyear) • Returns: 0 if vaccination date after date of birth 1 otherwise
The vacgivenUDF • Purpose: checks if the vaccination is given or not • Syntax: vacgiven(xvar) • Returns: 1 if vaccination is given 0 otherwise
The vseq UDF (Editing Only!) • Purpose: checks that sequential vaccinations are in the correct order (e.g., that Polio 1 is before Polio 2) • Syntax: vseq(v1d,v1m,v1y,v2d,v2m,v2y) • Returns: 0 if vaccination 1 was given before vaccination 2 (i.e., everything is ok) 1 otherwise
The vmatch UDF (Editing Only!) • Purpose: check if vaccinations commonly given on the same date (e.g., Polio and DPT) were in fact given on the same date • Syntax: vmatch(v1d,v1m,v1y,v2d,v2m,v2y) • Returns: 0 if vaccinations given on the same date 1 otherwise
The endmess UDF • Syntax: endmess() • Action: in add mode displays options 1 “Review Questionnaire” 2 “Next Questionnaire” • Returns: 1 if data entry operator selects “Review Questionnaire” option from menu 0 otherwise
The alphachk UDF • Syntax: alphachk(alphamask) • Input: acceptable values for an alphanumeric variable • e.g., for WS7 alphamask is “ABCDEFXZ” • e.g., for IR2 alphamask is “ABCXZ” • e.g., for MN2 alphamask is “ABCFGX” • Assigned before entry to the function: alphavar
The alphachk UDF Actions: • check responses in alphavar are in alphamask • check responses in alphavar are in alphabetical order • ensure if ? is in alphavar, then it is the only response in alphavar • places each response in alphavar in the location defined by its subitem • e.g., for WS7, “ACEF” becomes “A C EF ”
Net Roster UDFs There are three UDFs that concern the Insecticide Treated Nets (ITN) Roster Clear_labels – Clears array of labels used by SetNet SetNet – Prepares array of possible persons sleeping under net for display CheckNet – Checks validity of responses for persons sleeping under nets
The clear_labels UDF Syntax: clear_labels() Action: blanks out all entries in two arrays: Labels = “” Codes = notappl Used in preparation for setnet Returns: nothing
The setnet UDF Syntax: setnet(xvarname, curnet) Action: Creates a list of household members and their line numbers that have not already been reported as sleeping under a net. Returns: Nothing, but Arrays Codes and Labels are set to the line numbers of the household members not yet reported.
The checknet UDF Syntax: checknet(xvar, xvarname, curnet) Action: Checks the line number (xvar) given as sleeping under a net with the list of household members and ensures that they have not already been listed as sleeping under a net. Returns: Error message number if an error was found 0 otherwise