Table 2

Main effects from mixed linear models

	SDQ emotional problems					RCADS anxiety subscale					RCADS depression subscale
	B	95% CI		P value	N	B	95% CI		P value	N	B	95% CI		P value	N
Model 1
Lockdown	−0.246	−0.542	0.050	0.103	298/149	−0.055	−0.335	0.225	0.699	371/162	0.736	0.458	1.014	<0.001	377/165
Responder	0.276	−0.056	0.607	0.102	298/149	−0.796	−1.077	−0.515	<0.001	371/162	−1.331	−1.610	−1.052	<0.001	377/165
Model 2
Lockdown	−0.161	−0.537	0.215	0.398	298/149	0.059	−0.284	0.402	0.736	371/162	0.580	0.239	0.920	0.001	377/165
Responder	0.274	−0.059	0.607	0.106	298/149	−0.796	−1.077	−0.514	<0.001	371/162	−1.302	−1.580	−1.023	<0.001	377/165
Gender	−0.025	−0.351	0.301	0.881	298/149	−0.033	−0.289	0.224	0.802	371/162	−0.328	−0.573	−0.082	0.009	377/165
Lckdwn*Gndr	−0.153	−0.552	0.245	0.449	298/149	−0.223	−0.580	0.134	0.220	371/162	0.249	−0.106	0.604	0.169	377/165
Model 3
Lockdown	−0.111	−0.505	0.284	0.580	296/148	0.108	−0.238	0.455	0.538	363/158	0.722	0.376	1.068	<0.001	369/161
Responder	0.331	−0.006	0.668	0.055	296/148	−0.790	−1.069	−0.510	<0.001	363/158	−1.320	−1.602	−1.037	<0.001	369/161
Age	−0.013	−0.281	0.256	0.925	296/148	0.003	−0.212	0.218	0.979	363/158	0.027	−0.182	0.236	0.798	369/161
Lockdown*age	−0.215	−0.511	0.081	0.153	296/148	−0.222	−0.477	0.034	0.089	363/158	−0.031	−0.289	0.228	0.816	369/161
Model 4
Lockdown	−0.255	−0.551	0.041	0.090	298/149	−0.060	−0.340	0.220	0.674	371/162	0.733	0.455	1.011	<0.001	377/165
Responder	0.290	−0.040	0.620	0.085	298/149	−0.792	−1.073	−0.510	<0.001	371/162	−1.329	−1.608	−1.050	<0.001	377/165
SES	−0.140	−0.301	0.020	0.086	298/149	−0.060	−0.187	0.067	0.353	371/162	−0.051	−0.174	0.071	0.409	377/165
Lockdown*SES	−0.046	−0.245	0.153	0.650	298/149	−0.054	−0.233	0.126	0.557	371/162	−0.063	−0.241	0.115	0.487	377/165
Paired t-test
Lockdown	−0.195	−0.480	0.089	0.173	50	0.145	−0.136	0.426	0.305	51	0.713	0.432	0.994	<0.001	51

N for mixed linear models gives the (number of observations)/(number of individuals). Continuous variables of age and SES were z-scored, and lockdown and responder are binary variables. Lockdown is coded as before (0) or during (1) lockdown. Responder is coded teacher/child (0) or caregiver (1). Gender is coded as male (0) or female (1). Coefficients for binary variables (eg, responder, lockdown and gender) can be interpreted mean group differences. For example, B_gender=−0.025 indicates that when accounting for lockdown and responder, on average girls scored 0.025 less than boys. Because outcomes are standardised (M=0, SD=1), regression coefficients for binary variables can be interpreted similarly to a standardised mean difference. Sample sizes are lower in model 3 due to missing age information for some children.
RCADS, Revised Child Anxiety and Depression Scale; SDQ, Strengths and Difficulties Questionnaire; SES, socioeconomic status.