**9. Systematic reviews and evidence-based processes**

Systematic reviews involve comprehensive syntheses of collections of databases on specific topic. Good review reading may remain one of the utmost resourceful ways toward getting acquainted with advanced research as well as practice on several precise environmental/public health topics [76, 77]. The usage of explicit and consistent systematic methods (i.e., decision-making rules) in reviews decrease bias as well as decrease's chance impacts, hence providing a more trustworthy outcomes on which decisions are made [78]. One utmost important critique for public/environmental interventions in health is the "Guide toward Community Preventive Practices" (the Community Guide), providing a synopsis of contemporary scientific literature using a well-defined and rigorous approach where existing important research are units of analytical analysis [79, 80]. The Public Guide offers to addressed (1) What interventions statements are been considered or evaluated as well as what are their implications? (2) What interventions aspects could support clients in choosing between proven interventions set that are effective? (3) How much does this intervention cost, as well as how much does it costs in relation to probable impacts on health? A respectable systematic critique should enable professionals to comprehend local contextual situations required for fruitful implementation [81].

## **10. Economic evaluation**

The costs-benefits comparison to establish the most effective allocation of scarce resources is known as economic evaluation. We always carry out economic evaluations, albeit we rarely openly think about the process. It is a key component of evidence-based practice [82]. It could make available evidence toward evaluating the absolute alternative value of expenditures provided to the public/environmental health programs as well as policies. In cost–benefit analysis, all decision options based on costs as well as consequences remain valued in economic terms. Most frequently, placement on financial investment is related to an intervention likened to its effects on health, for instance, cases of disease prevented or saved life years. The absolute worth of some alternative interventions (for instance, health return on euro/ dollars invested) may show this method of cost-effectiveness analysis (CEA), [82].

### *'Silent Pandemic': Evidence-Based Environmental and Public Health Practices to Respond… DOI: http://dx.doi.org/10.5772/intechopen.100204*

Cost-effectiveness analysis (CEA) has turn out to be an increasingly essential instrument for academics, practitioners, as well as policy makers. Nevertheless, appropriate data toward supporting this analysis type are not permanently accessible, particularly in the context of potential public policies considered in health improvement [3, 36, 83, 84]. While, four (4) related kinds of economic assessment namely: cost utility analysis (CUA), cost-effectiveness analysis (CEA), cost–benefit analysis (CBA), as well as cost-minimization analysis (CMA). The four techniques vary chiefly in the mode of how benefits are measured. The cost–benefit analysis (CBA) measures the benefit in economic units (e.g., euros, dollars), while the cost-effectiveness analysis (CEA) measures the benefits in the relevant health unit (e.g., saved lives). Cost utility analysis (CUA) is a form of cost-effectiveness analysis (CEA) in which the benefits (such as life expectancy) are adjusted for life quality as well as quantified through a measure of health utility (typically quality-adjusted life years [QALYs]). Cost-minimization analysis (CMA) remain used once the two benefits interventions are the same, so the benefits measurement remains not a problem. Since cost–benefit analysis (CBA) uses the utmost "generic" outcome measure (several factors could remain measured through currency, together with the value of public health projects as well as educational interventions), it enables for a comparison of multiple programs. Its outcomes (see **Figure 3**) illustrate the possible results of the economic evaluation [2]. In view of the four (4) squares of the graph. Programs toward improving health as well as saving money (Quadrant IV) are certainly valuable as well as ought to be implemented. Likewise, programs that undermine health as well as costs affordability (Quadrant II) are unwelcome as well as must not remain continued or initiated. The two quadrants remaining (I and III) are in critical condition as well as where monetary appraisal can be more informative. In history, systems of environmental/public health as well as nations develop, interventions as well as programs began in Quadrant IV, through these programs that remain cost saving as well as improve and maintain health. Several initial public/environmental health interventions, like systems of sanitation, drop in Quadrant IV. When interventions are used as well as implemented, attention turns to programs in Quadrant I that improve and maintain health at an affordable cost. After all, as pressures in budgetary activities rise, programs in quadrant III are bear in mind: programs that lessen costs, nevertheless add loss toward health status. Aiming at the four (4) quadrants, the key question is, what is investment return

**Figure 3.** *Possible outcomes of an economic evaluation. Adapted from Raimi et al., [2].*

(or disinvestment) toward public's funds? Economic evaluation offers a means toward answering this pertinent question, so programs can be selected for the highest investment return.

Using the above conceptual framework (**Figure 3**) for the case of COVID-19 pandemic, numerous important conceptual economic evaluation elements can remain recognized. Before bearing in mind the procedure of conducting economic evaluation, it can be helpful toward determining the overall elements as well as all economic evaluations approach. The primary step is toward choosing the economic evaluation opinion. Each intervention could be thought of in several ways, often categorized as going from narrow toward broad. Health agencies or organization opinion should directly take part in delivering projected intervention. The next step which may be the insurers opinion, or payers, particularly in the health care industry, where consumers as well as payers remain two (2) distinct groups. The widest opinion is that of the whole society. Recommendations has been based on this wide-ranging economic evaluation opinion for all, as well as it is obligatory in quite a few countries having an established national health system. The viewpoint of the society is importantly suitable in public/environmental health as it seeks interventions designed toward benefiting taxpayers as well as the public funding the costs.
