Public Policy Adoption Index
International experience and scientific research indicate that physical distancing between people is the most effective way to contain the spread of the SARS-CoV2 virus that causes COVID-19.
The Observatory offers a public policy index that summarizes the actions of state governments to promote physical distancing. This index is calculated based on three factors:
1) the number of health policy measures undertaken by each government, from a list of 10 recommended measures;
2) the stringency of each of the measures taken;
3) the number of days between the date of the first case of COVID-19 detected in the country and the date of adoption of each policy measure.
The list of measures considered in the Observatory’s policy adoption index is based on a tool developed by the University of Oxford, the Oxford COVID-19 Government Response Tracker (OxCGRT) 5.0. The latter compares countries’ response to the pandemic, at the national level, by adding together measures of different kinds of policy (health, economic, etc.).
At the Observatory, we exclusively select health measures that are within the reach of sub-national governments and we codify their application in the different areas of each country. The measures are as follows:
- Stay at home requirements;
- Restrictions on the size of gatherings;
- School closures;
- Workplace closures;
- Cancellation of public events;
- Closure of public transport;
- Use of public information campaigns;
- In-state travel restrictions;
- International travel restrictions;
- Compulsory use of masks or face coverings.
For the calculation of our index, we code whether each measure is in effect for each day, from the date of the first case detected in the country. If it is, to consider the stringency of the measure, we code whether its application is partial or total. The possible values for each measure are “0” (not effective), “0.5” (partial/non-mandatory implementation) and “1” (total/mandatory implementation). Thus, each state receives a daily score between 0 and 10, resulting from the sum of the different dimensions.
The next step is to adjust the index value by the date of adoption of each policy. Since acting in time is essential to avoid an exponential increase in the number of cases, this weighting allows the pace of preventive implementation between different states to be taken into account. Earlier adoption from the date of the first case of COVID-19 results in higher values in the index. Conversely, a longer delay translates into lower values in the index.
Based on this methodology, the possible range of values in the policy adoption index is from 0 to 100. Higher values indicate that more measures have been taken, with greater rigor and earlier in the pandemic. Lower values indicate fewer, less stringent and later adoption of health measures to contain COVID-19. It should be noted that the maximum of 100 is a theoretical value, as it would imply full adoption of the 10 measures from the first day of the pandemic in the country.
In summary, the Observatory’s Public Policy Adoption Index is a precise portrait, updated daily, of each state government’s response to contain the spread of COVID-19.
The Observatory also reports the degree to which population mobility has been reduced in the different states of each country, compared to the period before the pandemic. Population mobility is an approximation of the level of compliance with recommendations to maintain physical distance between people.
The mobility reported in the Observatory is based on data provided by Google on travel to workplaces, supermarkets and pharmacies, parks and plazas, public transportation stations and shops and places for recreation. After excluding Google’s residential category, the index reflects the seven-day moving average for mobility data on visits to these sites. A description of the Google data is here: https://www.google.com/covid19/mobility/
The Observatory presents the moving average of the last seven days (instead of the daily value) for each state and day from the date of the first case of COVID-19 in the country. For the purposes of analysis in this observatory, the seven-day moving average is a more stable indicator, reflecting success in keeping the population at home regardless of small daily fluctuations.