Hi Statalist members,

I am having difficulty with testing for trends in proportion using survey weight. I am currently using a nationally representative dataset (thus svy command) and am interested in the change of e-cigarette harm perception (relative to cigarettes) over three waves (2018, 2019, 2020). The e-cigarette harm perception variable (relative to cigarette) is nominal variable with the following option available: "less harmful", "equally harmful", "more harmful", and "don't know".

I have looked at previous discussions in Statalist. Many points to the nptrend command, however the command is for ordered variable, while the harm perception variable I am interested in have "don't know" category (thus non-ordered).

Attached below is a fraction of my dataset. I would appreciate any help on this. Thank you very much.

Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input float(Harm_2018 Harm_2019 Harm_2020 Survey_Weight Unique_ID Strata)
1 1 2  120.4  1 1
2 2 2 1231.5  2 2
3 3 3  763.2  3 3
4 4 4  234.5  4 1
1 1 1  897.4  5 2
1 1 2  435.6  6 3
2 3 3  978.4  7 1
3 3 2  605.3  8 2
4 4 3  405.6  9 3
3 3 3    309 10 1
3 3 3  980.4 11 2
1 2 3  407.7 12 3
1 2 2  902.3 13 1
2 2 2  650.4 14 2
3 3 3  900.4 15 3
4 4 4 1380.4 16 1
1 1 1    104 17 2
2 2 2  201.2 18 3
3 3 3  809.1 19 1
4 4 4  785.6 20 2
1 1 2  804.5 21 3
1 1 2  203.5 22 1
2 2 1  709.7 23 2
1 1 1 1002.1 24 3
1 1 1  840.2 25 1
1 1 2  902.5 26 2
2 2 2  500.8 27 3
1 1 1  678.2 28 1
2 2 2  809.4 29 2
2 1 1  408.5 30 3
end
label values Harm_2018 Harm_2018
label def Harm_2018 1 "Less Harmful", modify
label def Harm_2018 2 "Equally Harmful", modify
label def Harm_2018 3 "More Harmful", modify
label def Harm_2018 4 "Don't know", modify
label values Harm_2019 Harm_2019
label def Harm_2019 1 "Less Harmful", modify
label def Harm_2019 2 "Equally Harmful", modify
label def Harm_2019 3 "More Harmful", modify
label def Harm_2019 4 "Don't know", modify
label values Harm_2020 Harm_2020
label def Harm_2020 1 "Less Harmful", modify
label def Harm_2020 2 "Equally Harmful", modify
label def Harm_2020 3 "More Harmful", modify
label def Harm_2020 4 "Don't know", modify
label values Strata Strata
label def Strata 1 "East", modify
label def Strata 2 "Central", modify
label def Strata 3 "West", modify